SOUND CARD was locked at 48K!!!!!!!!!!!!!!!!!!!!!!!!
When I converted 4832 to 4416 to MP3 sound was "fast." Unlocked card. Sound = OK
Never had this pblm with AA1.5. Seems AA 2.0 is very sensitive. Open anything outside of the pgm and it stops. AA1.5 - I can be recording / playing tracks back and surfing the net. Given as examples of activity / stability only. When I record / playback I try to keep the AA program as the only active thing in sight.
Strikes me that you are discovering the 'joys' of ASIO...
As far as everything stopping is concerned, that is a common problem for which there is an easy solution - go to Edit>Audio Hardware Setup and take the check out of the box that says 'release ASIO driver in background'. If you do this, then when Audition loses focus, recording and playback won't stop.
It's not Audition that is being particularly sensitive here - it's definitely ASIO that's being a bit of a one-trick pony. It's a bit like a racing car - very good at what it does, but you wouldn't want to take it shopping... and this is unfortunately reflected in the driver behaviour sometimes. And all ASIO drivers are by no means equal. Some will let you share ASIO channels across apps, some won't. Some lock the system up whilst running, others manage to get sample rates altered without having to resort to the card control panel.
So it's very much a case of YMMV, I'm afraid.