My external monitor's internal speakers and speakers work (HDMI), but none of my external USB DACs (SMSL SU-8 and xDuoo HD-5). This was not a problem until recently when I got updates from Ubuntu. I also have Windows updates and Lenovo updates. I am not sure which update has interrupted the sound. It may sound strange that a Windows or Lenovo update affects Ubuntu, but booting Windows interrupts my Bluetooth mouse connection in Ubuntu. Sigh.
The system seems to respond adequately when the devices are displayed in the "Settings" and the SMSL indicates that the sample rate is set to 48kS / s when connected (and nosig if not connected) and so on. However, sending sound through does not result in output. I get a good output on Windows, so it's no problem with the DAC hardware. I get a good output on the laptop speaker and the HDMI output speakers of the external monitor.
I tried TLP to prevent the device from being paused. I'm not sure if I did it right, but looking at the Pactl output does not indicate that the USB / DAC devices behave differently than the (working) HDMI devices.
otherwise "suspended" or "idle").
I am lost. Looking for suggestions
Other Noteworthy Things: In the past, I've tried (and apparently failed) to set up MPD and other things to send DOP / DSD to my DAC. Despite my mistakes setting up DOP / DSD, the USB DAC buzzed perfectly, and standard PCM was sent by Firefox or Clementine or whatever.
thank you in advance