Help. Please.

I'm running KnoppMyth R4v2 on a Shuttle SN41G2 (nForce2) with a PVR-250. After much searching through these forums and elsewhere, I got my MythTV setup working beautifully. However, yesterday I lost audio from the PVR-250 and nothing I've tried will bring it back to life. I have poked around the IVTV forums, the MythTV site, and everywhere else I could think of or that Google led me, and I'm completely stumped. (Though, admittedly, given my level of expertise this shouldn't be too much of a surprise.)

Here's what I can tell you:

* I'm running the audio through the line out jack of the Shuttle.
* Everything was working perfectly until yesterday.
* When I noticed that audio was missing on Live TV, I checked the old recordings that I had made. I still got audio from these, as well as from MythMusic. So I know that audio still works from the box.
* I have messed with alsamixer and test_ioctl and can verify that mute is not on and that volume us up.
* New recordings made since yesterday have no audio. Therefore, I suspect this is a problem with the card itself.
* I don't recall rebooting before having this problem, nor did I change any other settings. The only thing I did to the box was to open it up and dust it with a compressed air. (We'd had workers in kicking up drywall dust.)

So, my questions are:

1. Could I have shorted something in the card when I dusted the box?

2. How can I check the PVR-250 audio from the command line? In other words, if I could isolate this as a problem with the card and not the settings, I would think that installing a new card (ouch to the wallet!) should fix the problem.

3. Has anyone else had audio stop like this after it had been working?

I was so proud of getting my box working and now I'm completely bummed that it's crippled. Any help will be greatly appreciated.

Well, I just tried a fresh install of KnoppMyth R4V3, tried all the test_ioctl input/output combinations, manually captured some frames - all to no avail. Still no audio from the capture card. I guess it just went bad. At least, I hope so. I'll be ticked if I get a new card and have the same issue, but that's the last thing I know of to try.

Sigh.

Yep, that was it alright. I installed a new PVR-250 card and everything now works again. I would have figured that the card would have stopped working altogether when something went wrong, but obviously that's not the case.

Thank goodness, 'cause I gotta get my Daily Show groove on.