Hi! I use the following csd for mixing wav files. The third parameter to the instrument (P3) represents the length of the the current file. What if I don't know the length of the files? In this case I work with files of same length, and I just want to mix them together... Regards / Jonas - - - ; csound -W -o test.wav sr = 44100 kr = 44100 ksmps = 1 nchnls = 2 ; *************************************************** ; Instrument 1 ; *************************************************** ; p2 = start position ; p3 = duration ; p4 = volume ; p5 = pan ; p6 = filename ; instr 1 ivol = p4 ipan = p5 * 1.570796327 aleft, aright diskin p6, 1 aleft = aleft * ivol * cos(ipan) aright = aright * ivol * sin(ipan) outs aleft, aright endin ; PARAMETERS: ; instrument, start position, length, volume, pan, file name i1 0 10 1 0 "beats.wav" i1 0 10 1 1 "mary.wav"