Hi there - 
 
I've recently experienced a horrible high-pitched feedback sound that seems to correspond to the audio engine in SPlat.  I get this noise when I try to arm a guitar track using TH3; I click the arm icon and then LOUD feedback comes through monitors  or headphones.  Unarming the track kills the feedback, as does turning off the audio engine.  Even if I don't have any audio tracks armed, I get a strange distortion from MIDI tracks as well, using BFD3, SD2, etc. at irregular intervals in a given session.  It might go on for 15-20 seconds then go away, and then return a minute later.  Again, I can make it stop by turning off the audio engine.
 
Probably related: I closed a recent session tonight due to this feedback, I went online to Groove 3 to see if any videos discussed this problem and found that the audio is sped up X10 in these videos.  Youtube, Soundcloud reacts the same way.  Is this the beginning of the end of my audio interface or perhaps something else?
 
Any leads appreciated.  In the mean time, I'm pricing out USB audio/MIDI interfaces....

if possible in your Tascam drivers you could set the latency lower. I have has this issues with my us1800 and us1200s.

I just read something like this recently on these threads and I believe it had to do with this guy using 2 sound cards at the same time causing a driver/AI conflict. My advise is to look at your windows soundcard and as a test disable it.
then open sonar and see if you still get this feedback. it makes sense really. sonar might be trying to use both soundcards at the same time, thus causing a type of feedback loop. have you tried a reboot
 
1- do you have or have had ASIO4ALL installed ?
2- What driver mode are you using ?
3- what devices are selected under Preferences > Audio devices >

I've had similar blips lately and just stop/re-ran audio engine and then OK for rest of session. I also have an old M Audio driver left on system that I don't use now so might remove if probmatic.
 

Thanks for the ideas, all.
 
Chuck, I disabled "Hi Definition Audio" from the Windows Device Manager and it seems to have gone away.  I assume thats one of the drivers you were referring to, and if so, you've nailed the source of the shrieking.
 
Hopefully it stays away.  Thank you.

For SOME folks, the HD audio drivers just don't seem to play well with others, and disabling it seems to work.
 
Hopefully, this will solve that issue for you, 
 
Bob Bone