The file may be being identified as invalid because it has rubbish (possibly a large ID3v2 tag) on the beginning of the file or it uses space between frames to store other information.

Neither of those appear to be the case with these files. They seem to be very standard files without any garbage between the frames, and no V2 tags. In fact the files had no tags at all until I added them.

There is one other thing I noticed. They are 22khz files instead of 44khz. Does that have something to do with it?

Tony Fabris
Empeg #144