Given that the new firmware prevents the bad audio
when doing ivtvctl -q0, but not when doing mythtv
recordings, I have been studying what mythtv is doing
to cause the bad audio.
I am using ivtv 0.4.3 for all my tests.

I turned on ioctl debugging in ivtv, which shows
several ioctls when myth starts recording.  I have
determined this one to be causing my audio problem:
IVTV_IOC_S_CODEC
I can now reproduce the problem by repeating the
following several times:
ivtvctl -cbitrate=6600000
(or whatever bitrate you want)
This does the IVTV_IOC_S_CODEC ioctl.
Just like our previous problem with ivtvctl -q0, this
toggles bad audio on and off in a random sort of way.

I am trying a very crude hack that seems to fix my
problem (may break other stuff though)
In cx25840-audio.c, I added a reset of cx25840
register 0x803 at the end of the set_audclk_freq
function.
In other words, before returning from set_audclk_freq,
add the following lines:
   cx25840_and_or(client, 0x803, ~0x10, 0x00);
   cx25840_and_or(client, 0x803, ~0x10, 0x10);

Now I never get bad audio from ivtvctl, and I'm
patiently waiting to see if mythtv is also fixed.

Also, I tried the recent suggestion regarding
newi2c=0, but that did not solve this toggling of bad
audio problem.

Jim

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