Hey all!

Just finished installing an older version of Sonar 8 Producer (will upgrade soon when I have the $$$) on my brand new custom built DAW PC.  You can see my specs below, but I keep getting the following error every time I start Sonar up:
"The following driver(s) either do not support the current audio format, or are in use by another application.  Please choose whether you want to disable them or use them anyway."  Then listed below in the box:  "Realtek HDA HDMI Out (WaveRT)"

Not sure what to do on this.  I'm sure this is a newb question, but all I've used up to this point was Cubase, and now that I've just built this new PC, I'm not really familiar with this in's & out's of all my new hardware/software.  I've also noticed that when I open some of the sample projects, I get a constant VERY audible popping/clicking.  At first I thought it was a sort of reverb synth fx, but then I noticed it occured on most of the projects I opened.  Then I wondered if it was my M-Audio monitors, but I played some of my other music and I didn't hear any popping/clicking.  Maybe it's some sort of latency issue???

Maybe it's the fact that my DAW interface is crap (Presonus Firestudio), but I'm only able to upgrade bit by bit as I get the money.  Any help would be appreciated!!!!  Thanks  :-)

Specs:
Sonar 8 Producer
Presonus FireStudio Project 10x10
Win 7 64-bit SP1
Intel i7 3770K
16GB RAM
AMD Radeon HD 7700 Series

Disable the Realtek.

Or, if you don't want to kill the motherboard's integrated audio altogether, just disable the RealTek's HDMI output specifically to avoid that message. 

Many users turn their computer's internal audio interface off entirely via Device Manager, others like to leave it enabled for Windows sounds. Myself, I completely disable the integrated audio as well as all Windows sounds and use my outboard interface for all audio.

Thank you both!  Sorry for the 'softball' question.  I'll probably disable it altogether.

So, do you think that's what's going on with the weird 'reverb popping' that I'm getting?  Maybe the two audio interfaces are colliding in some way?  I won't find out if that's the issue until I get home from work tonight, so I'll post back if that solves the problem.  Any other insight is always welcome.  Thanks!

Make sure you're using ASIO mode on the PreSonus.

The "reverb popping" is probably not related to the RealTek issue. More likely, you're just hearing brief dropouts because the CPU can't process the output data fast enough, a symptom often seen after inserting a convolution reverb. You should be able to increase your buffer size a little and get rid of it.