Following up on my post, where I did a fresh upgrade to 18.04 ...
Since then, I've done a few simalar, FRESH, upgrades without a problem with sound. So, I went back to my own system and tried a few things; I was tired of having to open a terminal and copy "pactl ..." I tried:
1. Purged Pulseaudio in Terminal with: sudo apt-get remove --purge pulseaudio
2. Rebooted and had sound, but no sound control in the system tray.
3. Reinstalled Pulseaudio with: sudo apt install pulseaudio
4. Immediately had no sound without using: pactl load-module module-detect
5. Repeated step 1 & 2; had sound
Knowing that Pulseaudio is only a control app for ALSA and wanting control in the system tray, I installed QasMixer (an ALSA GUI) with: sudo apt-get install qasmixer I think the problem is with Pulseaudio and the inability to get it configured correctly on some machines. There doesn't seem to be a way of troubleshooting or an easy fix.
Following up on my post, where I did a fresh upgrade to 18.04 ...
Since then, I've done a few simalar, FRESH, upgrades without a problem with sound. So, I went back to my own system and tried a few things; I was tired of having to open a terminal and copy "pactl ..." I tried:
1. Purged Pulseaudio in Terminal with: sudo apt-get remove --purge pulseaudio
2. Rebooted and had sound, but no sound control in the system tray.
3. Reinstalled Pulseaudio with: sudo apt install pulseaudio
4. Immediately had no sound without using: pactl load-module module-detect
5. Repeated step 1 & 2; had sound
Knowing that Pulseaudio is only a control app for ALSA and wanting control in the system tray, I installed QasMixer (an ALSA GUI) with: sudo apt-get install qasmixer I think the problem is with Pulseaudio and the inability to get it configured correctly on some machines. There doesn't seem to be a way of troubleshooting or an easy fix.
Now I have both sound and a controller again.