[Alsa-user] dell l702x pin routing

[Simon M. <sma...@ma...>]

Hola - I have a relatively new notebook (L702x) which has an alc665-based HDA device.

The out-of-box configuration for ALSA in the current upstream kernel (3.0.1, ALSA v1.0.24) seems to do something which puts the left speaker to sleep at unpredictable times - and leave it there, and equally unpredictably wake it up again; it's always a soft fade-out/ fade-in transition when this occurs, never a hard off (and never any crackle or pop as it happens) - exactly as if the audio is being slowly set from balanced 50% left 50% right, to, 100% right (or back).

Interestingly enough once this has started happening, the same will happen if the factory-installed Win7 x64 image is warm-booted (to restore sanity you need to go into the Windows audio control panel and carefully reset each setting - both the master volume level, and the individual L/R balance levels); ditto with the Dell diagnostics tool (after the sound chip has entered the twilight zone, tests which should produce audio on the left speaker instead produce _only_ right-side audio for either L-only or R-only tests).

My initial guess would be that the pin/ mixer routing is not quite correct for alc665 using "auto" config and that perhaps as a result verbs are being sent to something they oughtn't be; this thought is bolstered by the lack of an individual level control for the subwoofer (which the Windows drivers can definitely control - whether this is through _input_  tweaking or not is not apparent; the Windows drivers - "hdxsg" - are infested with a SRS software shim/ preprocessor, so all bets on my side are off).

I have far better luck after overriding model= - for the moment I've picked 3stack (I have no surround-sound receiver at my disposal to test 5ch/6ch modes on, nor do I own any digital receivers - only the fixed speakers in the notebook, which, it must be said, are glorious, and a pair of equally glorious Sennheiser headphones).

In any case I've uploaded the alsa-info output as ...

 http://www.alsa-project.org/db/?f=b3a21e8487fe000edb4380cd4b91999c21b4f4f6

... after cold-booting Windows, then painstakingly resetting all the audio levels, then warm-booting linux (with index=0, model=3stack set).

I'm hoping that someone will be able to help me take this further (cooking up a custom patch file is completely beyond me, as it seems is doing anything particularly clever with HDA_Analyzer beyond admiring the graph it produces) - so that I can regain the level control (or at least an on/ off toggle) for the subwoofer.

More importantly, it'd be nice to help fix the model=auto type in the process, so that anyone else fortunate enough to own one of these beasts can appreciate their JBL speakers without thinking they're suffering early-onset left-ear deafness.

I've also snarf'd the Windows driver install files (from the DriverStore directory) in case that proves useful - please contact me off-list if you'd like me to go look at anything in particular there.

Finally, I'd also appreciate being put in Cc: on replies - to keep mailbox spammage down, I've set the daily summaries flag on my list subscription.

Thanks and regards,

Simon