7359 2-in-1: No sound from speakers after BIOs update

Hi all,

Recently purchased a 7359 2-in-1, and have been more or less satisfied - except for one glaring problem: There is no sound from the speakers (and despite checking all the properties, etc) after the latest Dell BIOs update - WS-01.08.00.exe.

I have spoken repeatedly with Dell Service, who sought without success to find a solution, and I even did a full factory restore - nothing worked until (and after much aggravation and searching on forum boards...) - I downgraded the BIOs to a previous version: (01.06.00,A05 26 Feb 20167:37:58 AM).

I have the sound back now, but - this can't be acceptable for a factory fresh device, can it?

Also, as a side note, is there any way to enable stereo mix (recording online/waveout), as I've had on my previous Dell XPS 13 and Inspiron? It's not a "right-click-enable-disabled" issue either - it's just not there on this machine, unless I want to dare to add a registry value - not something for the fainthearted on a new laptop...

Suggestions, anyone?