Seems I may have jumped to conclusions. I use Poweramp to play my music when paired to headset or car. Today I played music with the stock app and got no cracking noises. It acted as it should. I'm curious if anyone else is using Poweramp to play their music? Seems it may be the culprit, at least for me. SO I suggest if anyone is having cracking noises, try the stock player of a different player and see if it continues.
Make sure you try the just the stock music application, maybe bypass the Car application. You could even try a 3rd party music player?
I was able to get my Bluetooth working again after unsuccessfully unpairing/repairing the device. I finally got it to work by doing a hard reboot. Uncheck the fast boot preference Settings > Power > Un-check Fast Boot then shut down and power up your phone. Not sure why this would happen, but I can finally make calls hands free again.
Turn off Fast Boot and then fully power down. Wait a bit and then power back on?
I'm having dropouts every 5 seconds when I stream music off my SD card onto a Bluetooth dongle I have setup with my surround sound, I tested my [ASUS] Transformer - no issues and my LG Optimus had no issues either. Just wondering if everyone has this issue and would it be fixed via software? As much as I love my new Evo, this is a pretty big issue since I listen to music off my phone all the time.
Also did some research switching off my wi-fi, did make it much better and tolerable but still having dropouts
Try another device with the StereoClip if possible to see if the issue still presents itself?
Turn off all of your radios (3G - halt background data as well, 4G, Wi-Fi, NFC, etc.) Any other RF devices and even the car itself can sometimes cause signal inconsistencies. The more you can limit variables the better.
I've got the LG tone around the neck Bluetooth headphones and I have not had any issues with calls nor have I had any music streaming issues.
I HAVE issues with audio streaming in the car (to which I have found a workaround) but calls sound and work fine. I submitted an e-mail to HTC and I suggest you all submit tickets on these issues.
HTC knows the phone has bugs and they are relying on information from us beta testers.

So please contact them. Don't just voice yourself here, please message them.
The response I received from HTC seems to suggest they are working on a maintenance release, and they already know about some issues...
Marc puts this very well in this post ^
Basically there are known Bluetooth problems with our new phones,
hopefully with an update the performance can be smoothed.
Submit a ticket to HTC if you can't find a work around or to just let them know you have a trouble that should be worked out. They may have some steps to try (like Safe Mode or something)
Jim,
I've an Infiniti 2012 QX56 and calls come through fine, however the music does skip.
This is the workaround which works:
Make a call thru the Infiniti Bluetooth system.
Once it connects, just hang up (so don't call your spouse or boss..

)
Then start streaming Pandora, Tune-in, stock music player, etc etc and so forth.
This has worked each time I wanted to stream music from the LTE. The steering wheel controls work nicely and when I turn off the trucks head unit, the phone stops playing (play button changes to pause button).
lt should work for you Jim..
Not really related to your situation, but a
really brilliant little workaround by Marc. Maybe you can try it out, or find a similar fix?
_______________
Car Manufacturer and Stereo Brand could possibly play a role?
And last. Ensure your stereo and AUX port is properly grounded. Many cars can produce Ground Loop Interference or electromagnetic interferences with radio transmission/reception.
Also Note: if you have a cable or some adapters in line, test different cables or skip the adapters to eliminate some variables.