For a while I was having issues on my XPS 13 9350 DE where the sound would stop working and only "Dummy Output" would be shown under audio outputs. This would usually be fixed by a hard reboot. However recently this had failed to fix the issue. It seems no sound cards can be detected and ``aplay -l`` returns

``

aplay: device_list:268: no soundcards found...

``

I went through many troubleshooting threads and reinstalled drivers, replaced configuration files and more. 

Finally, I just did a full system restore of Ubuntu using the recovery partition and the same issue persists so I'm thinking now this may be a hardware issue... 

Any insight here would be appreciated.