Hello everybody, for my first post on this list, I have a question about Sysex. I work on an USB Audio device and I want to send a lot of SysEx from it to a computer. It works fine on Mac OSX and on Windows computer which have single processor. But when I use a multiprocessor computer, some sysex are corrupted. The symptom is: it cut a part(near to 20 bytes) of one sysex (between 0xF0 and 0xF7) and put it at the beginnig of the next one (before 0xF0). I looked at the data with an USB analyseur and all is ok on the bus. So it seems to be a problem with the USB driver. I have to precise that it happens also on single processor with hyperthreading. I guess it is a thread synchronisation proplem but I still don't find where it is. Does anyone have such kind of problem with the Windows default driver? Thanks, Kevin