My local installer has tried twice to get the USB adapter to work with my external hard drive. After the first attempt we re-formatted the drive to Fat32 so it could read it. Guess what? It didn't work! They did get a flash drive to work though. Same file format, FAT!
I know some people are running and external off their Pioneers and we are leaning to the problem being the USB adapter, well especially today as we plugged it into a Sony head unit with a front mounted USB slot and it powered up the drive and was reading it.
If anyone has any ideas please send them my way.