Found a 2.5mm -> 3.5mm plug laying around tonight. Recording worked okay by default, but I made the mistake of trying to "make it better", and broke the recording functionality with alsamixer.
Took me about an hour or so to get it back, and this page was one of the first to show up in my google search. For the record, as of now, I couldn't really find anything helpful on google, so I thought I'd post my settings below.
I'm using sox/rec/play for recording through a cell-phone microphone/headset. By default debian's precompiled "sox" won't record direct to mp3 I don't think... so I've started to rebuild that. ./configure shows that it can't find the "lame mp3 writer"... oh well, that's off-topic.
The alsamixer-controls:
Headphone 100 (just headphone volume, doesn't matter)
Headphone Playback ZC (00)
Bass0 <--------> 100 (doesn't matter)
Bass Boost (Adaptive Boost)
Bass Filter (200Hz)
Treble 100
Treble Cut-off (4kHz)
PCM 100
Mic Boost 100
Mono 100
Mono Mixer Left (0ff)
Mono Mixer Left Bypass (Off)
Mono Mixer Right Bypass (Off)
Mono Mixer Right Playback Switch (Off)
Mono Playback ZC (Off)
Playback 6dB Attenuate (Off)
Playback De-emphasis (44,1kHz)
Playback Invert (off)
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Capture 100 [[ NEEDS TO BE ENABLED WITH SPACE BAR TO RECORD ]]
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Capture 6dB Attenuate (Off)
Capture Polarity (Normal)
Capture ZC (Off)
3D 100
3D Lower Cut-off (200Hz)
3D Mode (Capture, Playback)
3D Upper Cut-off (1,5kHz, 2,2kHz)
ALC Capture Attack Time 60
ALC Capture Decay Time 60
ALC Capture Function (Off)
ALC Capture Hold Time 100
ALC Capture MAX 100
ALC Capture NG (on)
ALC Capture NG Threshold 90
ALC Capture NG Type (2,2kHz)
ALC Capture Target 100
ALC Capture ZC (On)
Bypass Left 100
Bypass Mono 100
Bypass Right 100
Differential Mux (Line1)
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Jack Function (Headset) [[ line/mic don't work for cell-phone headset ]]
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Left ADC 100
Left ADC Mux (Stereo)
Left Line Mux (Line 1)
Left Mixer (on)
Left Mixer Left Bypass (off)
Left Mixer Right Bypass (off)
Left Mixer Right Playback Switch (off)
Left PGA Mux (Line 1)
Out3 Mux (ROUT1)
Right ADC 90
Right ADC Mux (Stereo)
Right Line Mux (Line 1)
Right Mixer (on)
Right Mixer Left Bypass (Off)
Right Mixer Left Playback Switch (off)
Right Mixer Right Bypass (off)
Right PGA Mux (Line 1)
Right Speaker Playback invert (off)
Speaker 100
Speaker Function (Off) [ doesn't need to be ]
Speaker Playback ZC (on)
ZC Timeout (on)
I'm using "rec -r 24k -c 1 filename.aiff" to record an aiff sampled at 24kHz. The default of 8kHz is really poor quality haven't tried higher sample rates, 'cause I don't really need them yet.
It's late at night, so I could be wrong, but I think some of those switches will disable the recording; the bypasses can enable monitoring, but not sure if that works whilst recording. I didn't get the latter to work.
This is pretty much the first time I've managed to record audio since I was using the sharp rom, and this works a lot better.
