Originally Posted by ISCjonny
check the format. make sure it is formatted FAT32/FAT16. Sometimes the drives are preformatted NTFS.
Thanks. Actually that was the first thing I checked. I think most USB drives are actually pre-formatted FAT32 now (which these are). I bought 2 of the Verbatim 32gb drives and both are showing the same issue only with my IS250C audio system. A Kingston 32gb I had with data on it and just a few mp3 files worked (slowly) and the Patriot 16gb I had been using never had any issues.