Let’s Debug It: Hacksaws are Your Friend
Sunday, December 21st, 2008 | Author: lisaksimone

Clearly, all good things go bad when least expected. I was playing CDs extremely loudly one night and my fun came crashing to an end when the CD player began emitting disturbing grinding noises. Not at all in sync with the beat. In fact, there was no more beat.

Okay, I thought, I’d just inserted two new CDs before the grinding began. Maybe, like a DVD or CDROM, it didn’t quite seat right in the tray - let’s redo.

Wrong. Not only could I not eject the CDs, I couldn’t stop the grinding noise and couldn’t turn the unit off. It finally stopped when I pulled the power cable, but sadly resumed said grinding after power cable reinsertion.

Okay fine. Bag the music for the evening; let’s watch TV. Ah, nice try. Audio for all our electronics also goes through this system.

It’s either Grind-Grind, or silence. Some folks on the internet suggested 1) throwing it on eBay or 2) throwing it off the balcony. Shall we have a go at it a bit more nicely first?

The offending electronics

Our audio system is an old Bose system with the little black cubes mounted all over the room and the nice bass thumper on the floor. It sounds pretty darn good. TV, DVD, VCR, CD Player, AUX for the iPod, etc., all nicely routed through the system (with, I’d like to add, only one remote control).

Bose Lifestyle System

Bose Lifestyle System

So what are the symptoms?

  • “Grind-Grind. Grind-Grind.” Clearly sounds like motion or something in two directions/actions. Maybe CD in/out?
  • I’d just exchanged two CDs in the magazine. This player has a 6-CD magazine - I’d just ejected it, exchanged two CDs, and reinserted it. I heard the normal sound of the magazine loading back into the machine.
  • I hit Play, then hit the CD button to skip to the second CD. I heard a CD loading. Then abnormal pause. No music played. Then frighteningly, Grind-Grind, short pause, Grind-Grind, short pause. Repeat ad infinitum.

A little brainstorming and hypothesizing first

Let’s think a bit before rushing in - establish the State-of-the-System. Some initial thoughts - is the source of this problem electrical or mechanical? Software related? (The symptoms clearly sound mechanical, but who knows at this point. The system is at least 10-15 years old - how advanced could the software be?) Looking at the small 1-line LED screen, I could see that some segments were very slightly lit. I couldn’t tell what they might say.

  • Ah - the LED display segments are very dim but on.

Also, should we be careful that Grind-Grind might cause some irreparable damage to the system?

Plan of attack: Let’s proceed with the obvious control interface and reset stuff, while trying to minimize Grind-Grind. If that doesn’t work, we need to think more about what could have gone wrong.

Gathering Data - Obvious power and control stuff

Remove the magazine. For this system, you press down on a part of the magazine holder and a mechanical contraption of some sort allows the magazine to slowly eject. Seems mechanical but who knows. But when I try to, nothing happens. (Otherwise, this might be an amazingly short article.)

Bose 6 CD Magazine

Bose 6 CD Magazine

Muck with the user interface. I tried all the controls, starting with the remote. No button on the remote worked, including ON/OFF. Power is getting somewhere because the display is microscopically lit. No button on the unit itself worked, including ON/OFF. And the Bose has no option for the Three Finger Salute. So…could be electrical or software. It isn’t listening to either the RF link or the user interface buttons. Or OFF.

Step it up - power cycle. Pulled the power cord. Grinding (and all else) stopped. Reinserting the plug caused immediate resumption of Grind-Grind.

So, I think, when is a power cycle not a power cycle? With the evolution of “smart” electronics (and manufacturers who no longer believe the OFF button should actually turn the unit OFF without saving stuff, phoning home, and whatever else happens when you hit the power button), I think about the paaaaause that some electronics need to really turn all the way off/reset/whatever.

(Example: when cell phones really hang, pull the battery wait for any internal capacitors to completely discharge before reinserting. This puts the down in power down. When you reset your modem/wireless … turn off router, turn off modem, waiiiiiiiiit, turn back on modem, waiiiiiit for reacquisition, turn on router. …. “Waiiiiit” being just the right amount of time to clean the litterbox.)

A nice long pause between UNPLUG and PLUG doesn’t work. Grind-Grind.

  • Problem seems more and more mechanical. Some part of the system receives power - at least juice for one motor (for said Grind-Grind) and to very slightly run the display.

Gathering Data - What could cause Grind-Grind?

Grind-Grind sounds mechanical but could be caused by many things. Let’s listen to what it tells us. The noise clearly has two parts that sound nearly the same. Grind-Grind. Short pause. Grind-Grind. Short pause. Lather rinse repeat.

Things that cause two-part sounds: An obvious culprit is a motor that might be attempting to completely insert the magazine, and then eject it if something didn’t “work right.” Or, a motor that moves the CD in and out of the magazine to play it.

Hmmmm - another hypothesis - maybe I didn’t seat the CD correctly in the magazine. Is the player unable to extract the CD but just keeps endlessly trying? Lemmee check. The magazine has a little plastic window with the numbers 1 through 6 imprinted on it, to line up with the slots for each CD. (Left side of pic.) After peering and turning my head this way and that, I cannot see a CD in slot #2 in the little window. And CD #2 was one of the ones I replaced. A good hint. CD #2 is involved, and it is at least somewhat removed from the magazine. I can’t assume it is COMPLETELY removed because the window is not at the side where CDs are extracted.

  • CD #2 is involved, and I can’t see it in the magazine window. It is extracted at least partly out of the magazine.
  • CD #2 is one of the CDs I replaced.

Where is CD #2? Now I get to thinking…could I have accidentally slid CD #2 into a another slot by accident, causing the whole thing to jam up? (Sheesh - I’ve had this system for 10 years and have never done this, but what the heck - it sounds possible. Remember how it was possible to cram two 5 1/4 diskettes into one of those “old” drives? ) So after more peering and squinting, I can see that the other five slots do, in fact, contain CDs. They are all correctly aligned in the center of each slot. So that hypothesis is out.

  • CD#2 is in the correct slot and it is not jammed in with another CD.

Where is CD #2? We have just established were CD #2 is not. To figure out where it is, we need to learn more about how the magazine works.

This magazine is odd - it accepts 6 CDs and is inserted into the left front of the machine. You slide it in a few inches, and then it grabs on and pulls it the rest of the way in (straight back). But the odd thing is its orientation - refer to the picture. Holding the magazine to push it in, the opening for the CDs is to the right. This makes sense - the CDs are pulled from the right side of the magazine into the right side of the system where there is enough room for th playing mechanism. Okay - magazine goes in to the back, CDs are pulled out to the right. Gotcha.

  • CD #2 is physically located somewhere to the right of the magazine. Either in position to play, or on it’s way into position to play.

Taking a break

At some point in the debugging cycle, if you haven’t identified/fixed the problem already, you’re gonna need a break. It is during these times when you are distracted by other things (driving home, cleaning the litterbox, having an adult beverage) that your brain folds, spindles and mutilates what you know you know, and presents you with stuff you didn”t know you knew. (Got it?)

I took a break. I think I was already having adult beverages anyway, so I dragged out some computer speakers and attached them to my laptop. Resumed my musical evening, albeit at a somewhat lower volume and less awe-inspiring and earth (floor) shaking environment.

The only thing that percolated to the top of my head was the anticipation of my husband’s expression when he found out that he was gonna experience the suspense of Ghost Hunters using the boring ol’ front-mounted TV speakers. I was must certainly to be ostracized as having fouled up the audio system on purpose in order to watch House or something completely mind-numbing in his opinion. He suffered through an episode of Bones lately…isn’t that one about debugging too? Sheesh.

Soundboarding - Describing the problem to a guru, co-worker, imaginary friend, teddy bear, thin air

Describing a problem out loud, even to an empty room, is a great brainstorming technique because speaking out loud forces you to present the information somewhat linearly and logically. (Emphasis on the somewhat.) Ya gotta think about it a bit. And that’s a lot better than not getting a hold of the reins and letting your brain spin in circles on it.

Then suddenly my husband came home. Ghost Hunters was still 3 hours off. I had a chance to survive.

So I described all the symptoms and what I had tried. Being a good engineer and debugger himself, he repeated it all. (This did not offend me, and certainly should not offend you. Mistakes are made assuming what someone else as 1) tried and 2) observed from the trial.)

He came to the same conclusions.

Then he did something I believe no man alive has ever done in front of a woman. He asked for the directions.

I swear to god, he asked if we still had the product manual. And being the organized and somewhat Type-A engineer that I am, I was able to locate it in approximately 6.4 seconds. After a quick scan, our problem was not listed. No entry having anything to do with Grind-Grind. The closest we found was something about an error message on the display, with the action to Bring the Unit to an Authorized Service Center, No User Serviceable Parts Inside.

Now, this thing is probably 10 years out of warranty. Do you think two engineers who like to take stuff apart are going to let this fine fine opportunity go to waste?

Expand the search - we did the black box testing, let’s muck with the insides now

Quick inspection showed no recognizable paths to entry. Just recessed holes that clearly required some tool that we didn’t have, to use in a location that we couldn’t see. But we did find three slots on the bottom with the stamped message “magazine manual eject” located somewhat sortof in the general vicinity of all three slots.

Aha! Let’s get that sucker out of there. Easier said than done. There was no obvious switch, lever, or actuator of any sort from what we could see through these little 1cm x 0.3cm slots. After 30 minutes of 2 engineers and 4 5 various kitchen and hardware utensils, trying to figure out how to Manually Eject, we couldn’t. ** Then my husband had to run out for something unrelated, so I decided to fiddle around some more. For about an hour, I tried to balance a flashlight in a tiny slot, peering in and wiggling the magazine to see what parts moved. There was a spring…implies the eject mechanism is in there somewhere. A thin black rod moved slightly, into an unmoving sheath. Perhaps under that tight ribbon cable. (Note, these activities put the F in Fiddle.)

** Butter knife, cheese knife, hat pin (I swear, an excellent tool), mini slotted screw driver, and picture hook.

After much poking and levering, and at least one new custom tool from the picture hook, I was able to slide the newly created tool diagonally in and up and pivot the tool against the side of the slot to slide a nearly unseen slip of metal casing a few millimeters….and the magazine slowly started to slide out. (And no, I am not sure I could have written that any more clearly without maintaining debugging accuracy ;-))

Yes! With anticipation, I watched, having conquered the elusive manual eject…and the magazine began to move, sliding as if through honey (really) and moved about an inch…and then stopped. Before it was even out far enough to grab with two fingers. Crap. So I’ve activated the manual eject, but now something else is blocking the magazine.

  • The magazine required not only a manual eject, but was blocked by something else mechanical. So far, nothing electrical or software is related.

What is preventing the magazine from fully ejecting? If I levered the magazine somewhat forcefully to the left, in a tiny slit I could see the shiny edge of one CD. CD #2 was stuck more than half way out of the magazine, to the right, in the direction of the playing mechanism. And since the CD is sticking out to the right, the magazine cannot eject. And the little tiny space where I can see the edge of the CD is too small to get any tools into. I also note that the CD is held in place by two rollers, one on top and one on the bottom, probably to guide it all the way into the playing mechanism.

  • The CD is mostly ejected from the magazine and correctly aligned between rollers, but not fully drawn into the playing mechanism. This prevents ejection of the magazine.

We have a slippery grip on the problem…the CD is somehow jammed in the player, which prevents magazine ejection, which also required manual ejection. In fact, the CD’s relative (and bad) position to the magazine looks suspiciously like its presentation in the marketing picture…

Bose 6 CD Magazine

CD Magazine with CD extended in suspiciously in the "stuck" position

What the heck is holding the CD in the player?

Remember Grind-Grind?

Don’t forget the original symptoms. We hypothesized that Grind-Grind might have been a motor repeatedly trying to insert/eject something. Originally I suspected it was a motor for the magazine itself, but now it might be for the CD. However, from the very little I could see of the offending CD’s edge, it didn’t seem to move in any synchrony with Grind-Grind.

  • Grind-Grind is somehow related to the CD rather than the magazine.

When you’ve got a hammer, everything looks like a nail

My husband came back home again. I am both elated that I figured out the gyrations to manually eject, but am stymied on how to deal with the CD-out thingie. After his own fiddling based on my hand-drawn internal layout of the manual eject, with arrow indications where to push, and which slot at what exact angle to hold the flashlight, (and 27 8-by-10 color glossy pictures with the circles and arrows and a paragraph on the back of each one…) he manages to duplicate the manual eject mechanism. (Really, it was strange and not at all intuitive. Interesting that something as useful as a Manual Eject would not be easily user-figure-out-able.)

We screwed around some more and then gave up. Now, my husband is an electrical mechanical guy and he has a machine shop among other things. Kinda like a MacGyver. So he took the whole thing to work the next morning, and that evening proudly announced that he had gotten the CD magazine out and fixed the player.

Cool! Yes! I was relieved that the system would be working again.

“So how’d ya get it out?” I asked.

“Hacksaw.”

?!?

“After I spend hours fiddling and finally figuring out the manual eject without destruction, you HACKSAW the magazine out of there???”

Thin and Svelte Hacksaw for those Hard To Reach Places

Thin and Svelte Hacksaw for those Hard To Reach Places

His expression was purely of the testosterone variety. Pride at solving a problem, Neanderthal dominance over lesser forms of home electronics, and lust for the opportunity to use large, sharp instruments; power or otherwise.

**Rolls eyes**

So I asked about the process, the results, etc. He had been able to determine that the Grind-Grind had something to do with focusing the laser on the CD. He wasn’t able to tell if the CD had been fully inserted, but probably not. Just enough for the system to register it was there, but not enough for the optics to be able to focus on the surface. And, he finally clarified, he’d only hacksawed the CD, not the entire magazine.

After CD “removal”, he’d blown out all the chunks and dust. On power-up, Grind-Grind was gone and the system appeared to be waiting happily to play some cool tunes.

Validating the (Ahem) fix

To complete the debugging process, we needed to validate the fix. We had tested that all other audio inputs were fine - DVD, TV, iPod, etc. Now on to the CD validation - he’d been able to remove the symptoms of the problem, but we weren’t sure he’d actually fixed the problem. To do that, we’d need to put ANOTHER CD into slot #2, attempt to play it, and see what happened.

At this point, I invoked Executive Control and halted the process. Whatever had happened required a not-so-subtle recovery, and I wasn’t interested in replacing the system if the next “extraction” ended up being more destructive than the first. I’ve ripped (as in copied, not as in spindled/mutilated) all my CDs to my computer, and I was fine using alternate methods of CD enjoyment.

What about the All Knowing Internet?

This is a theme with me - the internet is a good place to get some initial ideas, but blindly following the advice of folks out there who may or may not have a real clue requires a little validating yourself. While I’ll never truly know what caused our problem, I might have, if we’d decided to crack the case as others have done. Getting a useful answer means constructing a careful search string. Lest you be bombarded with inappropriate suggestions. Like:

  • “Eject the magazine, turn it off and on again, reinsert magazine, Viola!”
  • “Set on side, rap hard while pressing eject button.”
  • “Dissasembly of head unit may be required if you cant jam something into the cassette unit and forceably remove it.”

But a GREAT use of the internet is comic relief - sarcasm is always welcome in my neighborhood. Real life suggestions:

  • “How about a good HAMMER? that’s what I’d use, heh.”
  • “I was think more along the lines of dropping it off of a balcony”
  • “eBay the darn thing”

On the other hand, there are some suggestions that do seem to have some merit, including getting the case open (it is glued together) and reinstalling a plastic gear that has slipped. Many less technically savvy folks have contacted Bose and paid the $200 service fee, with varying degrees of success (disgruntlement).

But isn’t pulling out the ol’ hacksaw so much more fun?

The Aftermath

I had some cool tunes in the player, so I had to ask. “Okay…which CD was it?”

“Couldn’t tell,” he said. “All the writing was scraped off.”

Actually, he admitted the CD had been completely destroyed.

What?!? I’d expected two unequal pieces, a circle split along a chord.

“The CD was right inside that slot. How did you get the hacksaw in there in such a way that you managed not only to scrape off the singer’s name, but to completely destroy the disc beyond recognition?”

(Sharp tools. Grunt. Tim the Tool Man Taylor.)

On further interrogation, he was able to recall two words, and I realized it was a Susanne Vega CD I got in college. Her first. I’d seen her in a little intimate performance before she hit it big. A CD I loved and had not played in a while.

So he offered to get a replacement for Christmas. That’s a nice gesture, and I was touched. I thanked him, and went online to find him a link. “No longer offered by the manufacturer.” And someone is selling a new copy for $75.

Why couldn’t it have just been one of the mindless $11 mass-produced CD I bought last month???

Sigh.

≈ ♦ ≈

See the comprehensive list of All the “Let’s Debug It” Mysteries

Let’s Debug It: A Rabid War between Technology and Nature (Jet Skis vs Mangroves)

Let’s Debug It: My Internet Security Software HATES me, TOLERATES me, REVILES me. Evil BitDefender

Let’s Debug It: Alaskan Scuba Stuff and iPods Don’t Exercise

Let’s Debug It: A Cat’s Plea to Microsoft - “Can You Hear Me Now?”

Let’s Debug It: “No Ma’am (Idiot), You’re Calling from Line 2″

Let’s Debug It: Keyboards and Endothermic Mammals

Let’s Debug It: Hacksaws are Your Friend

Let’s Debug It: My Computer Plays “I’m Ignoring You Now”