diff --git a/src/sound/midi_opl4.c b/src/sound/midi_opl4.c
index eda264a39..25f44c9e7 100644
--- a/src/sound/midi_opl4.c
+++ b/src/sound/midi_opl4.c
@@ -436,7 +436,7 @@ note_on(uint8_t note, uint8_t velocity, MIDI_CHANNEL_DATA *midi_channel, opl4_mi
     const YRW801_REGION_DATA_PTR *region_ptr = &snd_yrw801_regions[0];
     const YRW801_WAVE_DATA       *wave_data[2];
     VOICE_DATA                   *voice[2];
-    uint16_t                      i = 0;
+    int                           i      = 0;
     uint8_t                       voices = 0;
 
     while (opl4_midi->gen_in_progress) { }