i used the render & have a stereo mp3 file on disk of a reaper project.... i use purewave asio drivers.. the signals from these drivers bypasses the windows kernal ... purewave drivers provide the most direct routing for computer based recording, developed by echo, they were used on the old layla 20 interfaces.. bottom line is, when using purewave drivers, i have no access to output signal for winamp, window players & such,,, so to test, i'd need a mp3 player that had asio outputs... this is so complicated !!! i guess i could move mp3 file to my reamote computer & play there, but i am really trying to all this to work on 1 computer.. i could switch asio drivers back & re-gain control over winamp or windows player... really don't see any upside to doing that.. anyway, got this far... many thanks, ted Student: School of Hard Knocks