I bought this little handheld multi-track recorder called the Korg PXR-4. It encodes audio to SmartMedia using MPEG-1 layer 2 or MP2. The MP2 files it creates load just fine into audio apps like Sound Forge. Unfortunately, if you attempt to transfer a file that originated elsewhere and was converted to MP2, or one that originated on the PXR-4 but was edited, it often will crash the unit with a DSP:0015 error (not that I expect anyone outside of the Korg design team to know what this really means). To attempt to see what will make the unit crash I've recorded a number of test files with sweeps at various levels, noise, speech, etc. Oddly most of these work fine, but when I take an actual music track say from SONAR, and covert it to the proper MP2 format, it will still crash the unit within 15 seconds. I got a copy of the ISO document that describes MP1, MP2, and MP3 and have written a program that will scan an MP2 file and read the headers (which is not very exciting, but easily enough done). I don't believe the compatibility has anything to do with the original or copyright bits because I've tried various permutations of that and it seems not to matter. I'm guessing that the h/w encoder in this unit is only able to do a subset of what a full-fledged encoder really needs to do, but since they've balanced it out with a matching decoder it doesn't matter so long as you stay on the unit. My question to you experts - what could it possibly be?