diff --git a/src/hardware/mpu401.cpp b/src/hardware/mpu401.cpp
index c5a2a77f..4afa5691 100644
--- a/src/hardware/mpu401.cpp
+++ b/src/hardware/mpu401.cpp
@@ -605,7 +605,7 @@ static void MPU401_Reset(void) {
 	mpu.state.cmask=0xff;
 	mpu.state.amask=mpu.state.tmask=0;
 	mpu.state.midi_mask=0xffff;
-	mpu.state.data_onoff=0;
+	mpu.state.data_onoff=-1;
 	mpu.state.command_byte=0;
 	mpu.state.block_ack=false;
 	mpu.clock.tempo=mpu.clock.old_tempo=100;