Thought I might like to update this thread. I recently encountered some other problems with the amp.
1) Any form of loud listening introduces clipping. Whether I turn down the DAP and turn the pot or turn up the DAP and turn down the pot, there seems to be so solution. He said to turn down the DAP and turn up the pot, but that hasn't been doing it for me, whatever I listen to. At first I thought it was the song files, but they're all lossless and sound fine without the amp.
2) I also noticed a heavy bass emphasis. What with the SR60s, it's a welcome change to fill the Grado's bass gap, but I myself am more of a upper-mids kind of guy in terms of violin and the electric guitar. He also explained this to me, but regardless, I'm not feeling it.
Anyone else experience these problems? I hardly even use mine anymore because of the major clipping. I emailed him and he said developments for the PA2V3 are a few months away from their start, but I think things are generally looking upwards.