[PLUG] No sound

[Ben Koenig]

On 12/20/20 9:58 PM, Dick Steffens wrote:
> On 12/20/20 9:42 PM, Bill Barry wrote:
>> On Sun, Dec 20, 2020, 11:34 PM Dick Steffens <dick at dicksteffens.com> 
>> wrote
>>
>>> With the turntable unplugged PulseAudio sees a port labeled Line Out
>>> (plugged in). When I plug in the turntable it adds a section for 
>>> PCM2900
>>> Audio Codec Analog Stereo in a port labeled Analog Output. The Line Out
>>> (plugged in) section is still there. BTW, I also tried powering up the
>>> turntable, but it had no effect.
>>>
>>> Now my question is, is there a way to change the behavior?
>>>
>> What happens in the Configuration tab of PulseAudio control when you
>> connect and disconnect the turntable?
>
> It starts with two sections labeled Built-in Audio. One of them says 
> Profile: Off, and the other says Profile: Analog Stereo Duplex.
> When I connect the turntable a third section appears labeled PCM2900. 
> It says Profile: Analog Stereo Duplex.
>
> Clicking on the down-arrow provides a list of options, some input and 
> some output. If I select Off, the sound returns to the speakers. Sound 
> remains playing through the speakers when I select Analog Stereo 
> Input, or Digital Stereo (IEC958) Input. I assume, coming through USB, 
> the latter is the one I'll want for recording an LP.
>
> This may solve the problem. Just to see, I left the USB cable plugged 
> in and restarted the machine. When it came up, PCM Audio Codec still 
> had a profile Digital Stereo (IEC958) Input.
>
> So maybe it just needed to be told what I want it to be and will keep 
> that going forward? Hope, hope.
>

By selecting "Off" for the Built-in Audio profile you effectively 
disabled your built-in motherboard sound chip. You basically told 
Pulseaudio to not include that device in the list of available audio 
devices which results in it selecting the next audio device down the 
list when an application starts playing sound.


This also explains why it worked when you selected "Analog Stereo input" 
and "Digital Stereo (IEC958) Input". Both of those options tell 
Pulseaudio that your card is to be used for input ONLY so it never shows 
as an output device. Since the problem was audio not playing through the 
correct device setting the device to input only has the same effect as 
turning it off.


You can achieve the same result by changing your default sound device to 
whatever your speakers are plugged into. You'll also need to check the 
application's stream and make sure it is using the "default" since pulse 
allows individual apps to play through a different card if told to do so.

-Ben