I am having a problem with my USB midi interface, a midiman midisport 4x4. I have 2 gigastudio PCs and have had thye same problem with both. They have different CPUs, both have 520 meg Ram, one is SCSI one Ultra ATA. The problem is one of loud clicking thru audio when the midisport is connected. Detach the USB and no problem. One machine has Gina analog outs, the other has Digi96 lightpipe outs. The clicks register as overload on my protools interface.
This should be a FAQ I guess; but Giga is notoriously bad with USB ports & MIDI. I just sold my Midisport 2x2. USB MIDI is a great idea but the polling etc makes it unbearable for Gigastudio (I believe there\'s an RME article on their website about the curses of USB & MIDI). You\'re far better off just using your soundcard MIDI (e.g I went back to just using an SBLive) or some sort of serial port MIDI device, or a decided MIDI PCI Card.