Yeah, Mac's probably nailed it. This FAQ should help. Read FAQ 128 as well. My comment was relevant to the MME driver, but I had it backwards. For a DXi synth, the thru setting should be disabled. If still no sound (with MME), check the DXi interface itself to make sure it's being triggered and channel volumes are not zeroed/muted. Post back if none of this stuff works. -Ron