I have had a similar problem with a nevo I am currently programming for a client. I have installed Nevo media manager on a local PC in house which he is going to use as a MP3 file server for his Nevo & a Dlink DSM-320. When I initiated a seach of his MP3 directory with Nevo media server the server software would recognise the number of files in his directory but when the search was finished it showed there were no MP3's in the directory. After trying differn't methods of ripping MP3 files I gave in and called the tech support at our distrubuter. He had not heard of the problem but soon tracked down the problem to the ID3 tags of the MP3 files. ID3 tags have two versions ID3v1 & Id3v2 Nevo media server apparantly needs files with ID3v1. You can check the version on the ID3 tag with an MP3 tag editor like "MP3tag"

I use the Audio ripper "CDex" and it allows you to choose which version of ID3 tag it gives your audio files. I've just set it so it encodes with both version 1 & 2

I hope this is of some help.