On 01/07/2017 03:34 PM, Fred Smith wrote: > On Sat, Jan 07, 2017 at 02:11:47PM -0800, Alice Wonder wrote: >> On 01/07/2017 01:42 PM, Laurent CREPET wrote: >>> On Sat, Jan 7, 2017 at 10:23 PM, Alice Wonder <alice at domblogger.net> wrote: >>> >>>> Logitech H540 headphones were working fine. >>>> >>>> Suddenly stopped. > > On my C7 Mate system I have what may be the same issue: > if the "sound preferences" app (aka Mate Volume Control) is already > running at the time the USB headphones are plugged in, the USB phones > appear as disabled. > > OTOH, if the phones are plugged in, then the Mate Volume Control is > started, they are not listed as disabled. I leave the headphones plugged in all the time, they were working fine and just recently stopped after doing some work in Audacity, I am wondering if Audacity disabled them for some reason but if it did, not while I was using it. I'm at a loss as to what triggered them to be listed as disabled. > > When that first began happening (a year or two ago, I think) I > posted on the Mate forums and someone said he thought he saw the > bug and would do a build to fix it. unfortunately his build did not > fix it, and it has remained. > > AFAIK, I have no sound hardware blacklisted (where do you blacklist it?) > I have an Nvidia card with HDMI output, and it shows up in the sound > app, but since I don't do HDMI video on this machine I always just > ignore that device. Blacklist is in /etc/modprobe.d/blacklist.conf On mine it consists of blacklist snd_hda_intel blacklist snd_hda_codec_hdmi I think only the first is necessary to prevent the useless sound chip from being chosen but I have both lines there.