i think it's important to keep in mind that the microphone is a bit of a bonus. it replaced the questionably-useful light sensor relatively recently.

This is jut me, but i never saw the mic as a key feature (ala http://www.chumby.com/story)

I've also followed Bunny's posts about the quest for quality in the mic http://www.bunniestudios.com/blog/?p=187 to trust that it'll work when that functionality is supported.

My tests show an overwhelming amount of noise, with or without me speaking.  BZZZZZZZZZZZZZZZZZZZZZZZZZ throughout the recording.  Either my testing methods are not valid or there is a hardware or driver problem.  I'm doing a very simple test like this:

cat /dev/dsp > /tmp/output.txt
<talk or whatever>
Hit Ctrl-C to stop recording.

To playback I did this:
cat /tmp/output.txt > /dev/audio

I encourage everybody to test their system this way and let me know how it goes.  I mentioned above that I do not have a dedicated Linux box so I really have no way to test this outside the Chumby.  If anybody would mind doing this test, I would greatly appreciate it.   The problem I have is not with the audio drivers, potential hardware problems, etc.  It's with the fact that Chumby.com's tech support is unwilling to assist in any way. 

Imagine if Dell tried to pull this by saying "well, we're not currently supporting the hard drive...."

-Bob

Are you sure that's the proper way to record data from the microphone and play it back?

Huh?  No, since there is no software currently using the microphone just yet, why would you insist on saying it must be supported already?

That's just insane...

At the command-line, we recommend you use 'arecord'.

That is because this is not how you are supposed to interact with the microphone.  See my above hint as to reading the alsa documentation, and the other hint on how you shoul use the arecord program.

As gregkh has pointed out, this is simply not the proper way to use the driver.  The chumby drivers are built to support ALSA.

To do this test properly, you should do:

# arecord -f cd /tmp/output.wav
(talk, hit Ctrl-C when done)

# aplay /tmp/output.wav

As I mentioned elsewhere, the gain is pretty high by default, so you may get some clipping if you talk too loudly.

The microphone goes through two QA checks at the factory, so we're pretty confident that it works when used properly.

Duane, thank you.  This test worked fine.  I grew up with Linux and the OSS driver.  Alsa is kinda new to me, but that's why I'm posting here for help.

Tommy, please examine the feature set closer, here it is for you:
Release Hardware Version Code 0307 "Ironforge" — main board

Release code 0307 supports the following features:
Note: all specifications are subject to change on future releases

    * 350 MHz ARM controller (MX21 by Freescale)
    * 32-bit 64 MB SDR SDRAM running at 117 MHz bus speed
    * 64 MB NAND FLASH ROM
    * 320x240 3.5" TFT LCD with 3-state LED backlighting
    * Touchscreen input
    * Stereo 2W speakers with hardware mute
    * Headphone output with headphone presence detection
    * Microphone input with programmable AGC
    * Squeeze sensor (to pick up when you squeeze the chumby)
    * 3-axis Accelerometer (+/-2g range @ 12 bits resolution)
    * Three USB 2.0 full-speed (12 mbps) ports, one on the main board and one on the outerware electronics
    * 802.11g connectivity via a USB dongle plugged into the main board
    * Circuitry to detect the presence of wall adapter power and auto-fallback to backup battery power
    * Switching power supply network that can eat between 6V and 14V
    * Cryptoprocessor for authentication and system management (full device access over JTAG)
    * Daughtercard ID management system for device personalization
    * Available SPI bus on the chumbilical bus
    * Serial debug port set to 38400 8N1

-Bob

This is true, I will be keeping it.   I've been a Linux coder (including various bits of kernel code) since 1993 -sorta.  Right around 1996 I kinda gave up on Linux for commercial UNIX.  Due to a previous job starting in 2002 had to get up to speed again and get certed as a RedHat weenie, so there was a good gap in there.  I missed out on the whole ALSA thing.  Sound was not something I ever had to worry about since writing fm syth chip code back in '93 (the console beep annoyed me so I "fixed" it) so I didn't even know about it till very recently.

My issue was not that it worked or not.  It was that tech support said that it's not supported and that I was on my own when all I wanted to do was verify that it worked.  If it was defective hardware, they sure as heck better do something about it.  Obviously we determined that it's not defective, all is well, etc.  I just didn't appreciate being abandoned by the company I just forked over hard earned money to, just so I could write software (for free, I might add) that will bring value to this product.  It was a bit of a slap in the face, ya know?  I realize you (Duane) are probably somewhat removed from first line tech support, so I do appreciate your time on this.  I actually worked with the tech support guys for a few days on the AVS issue you guys had with the credit card verification that was kinda broken, just because I thought this product had some potential.  Usually my attention span would've had me onto the next big thing the first time my card was declined due to an "address mismatch", but not in this case.

Anyway, just to be clear, and to restate, I never had an issue with the hardware, or software.  It was the fact that tech support abandoned me and suggested I try here.  I thank everyone involved for helping me out on this issue, and I'm glad to say that my microphone works just peachy.

-Bob

Well, I guess I should make it clear that you were talking with Customer Service, not "Tech Support".  They are not trained engineers and most highly technical questions are referred to here, where the actual engineers hang out.

There is no classic "Tech Support" of the type you're describing.

Note that you're quoting the hardware specifications for the motherboard, which is not a definitive list of chumby "features" as currently exposed to the user.

All I can say about Duane, bunnie, and the rest of the people at Chumby: they are saints. They put up with a lot of crap over trivial things and stay totally calm and collected about it. I suppose they probably had a feeling there would be some of this because their product is so unique and people see what it should do and what its limitations are differently. You guys are a lot more patient than I am, that is for sure.