Have yet to try this with ProScan but I would look at the audio levels on your sound card and/or where you turn audio up or down on your PC. You have your recording audio levels and then you have your playback audio levels. And while one can look and indicate one thing the other may not be set right to do the other. I've never even seen the band scope that shows the waveform playing back yet in the software. But if it's showing the spikes and audio traffic and it's not just a flat, level recording, then it looks like you've captured the audio in the file I would think. Have you tried to take a sample recording and play it on some other type of player? Maybe you could put it on a flash drive and try to play it on another computer that is not a part of the current recording / playback setup?
These are just ideas and what I thought when I read your post, but as I said, I still haven't tried this yet using ProScan so there may be something else going on.
Brian (COMMSCAN)