The problem is Sonar, not the Tascam US-16x08 drivers.
I have spent the the evening tracking this down.
I tried the 16x08 with Reaper 5.11 with ASIO and WDM.
Both modes work in Reaper.
I then installed ASIO4All (ASIO4All just wraps the WDM
drivers) and Sonar worked! I could record with the 16x08.
Just to make sure ASIO4All really WAS taking the WDM drivers, I
then also connected my Tascam US-1641 and my US-1800.
All three interfaces were visible in ASIO4All and subsequently also
visible in Sonar.
I then did tests and apart from poor latency and a slight
out-of-sync between the 3 interfaces (easily fixable in post), I can
record from all 3 interfaces at the same time.
Standard ASIO does not allow multiple interfaces, WDM does.
So ASIO4All really is taking the WDM drivers.
Next I uninstalled ASIO4All, hooked Sonar directly via WDM/KS - and again
I get that constant white noise when I arm a track.
In conclusion, there is something new in the 16x08 drivers that
Sonar is getting wrong.
By contrast, Reaper and ASIO4All do it right.
Edit: I will repost this in the Problems forum.
post edited by jpetersen - 2015/12/26 18:16:48