Notes, a couple last comments and questions and then I've run out of suggestions:

1. Is your unit the M-Track or the M-Track II? The reason I ask is that one came out before the Avid purchase of M-Audio, and the 2nd one came out after Avid unloaded M-Audio. Prior to Avid, drivers were rock solid for those products. Can't speak to the post Avid product driver situation, but bad reviews about drivers are one thing that prevented me from buying the M-Audio M-Track Quad a couple of years ago.

2. Are you running a 64 bit version of PTPA? I didn't think such a thing existed. In order for the whole system to work together, the OS can be 64 bit, but I believe your application accessing the driver has to also be 64 bit if the driver itself is 64 bit. I didn't think there was a 64 bit version of PowerTracks Pro Audio. I believe that you can run 64 bit plugins through PTPA using Jbridge, but I think PTPA is a 32 bit application. Somebody step in here and dope-slap me if I have this wrong.

3. The output through the headphone jack you list above could be simply the analog pass-through that the device does for direct monitoring (latency free monitoring). In order to perform the test of whether the device is working correctly do these two steps:
a. You need to have whatever the knob is rotated all the way over to whatever is the non-direct label. On the M-Track II, it's the USB side of the knob. If you are getting output there, with it rotated all the way to USB, then you have audio passing through the device, through USB, to the computer, and then back to the device, and getting converted back to analog audio.
b. Use a digital audio source - that is, simply play a CD or .mp3 file that is on the computer through the device.

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