Genesis Plus GX: mono sound output

Author: cobaltgit

RetroArch/.retroarch/config/Genesis Plus GX/Genesis Plus GX.opt

@@ -52,7 +52,7 @@ genesis_plus_gx_sms_fm_channel_5_volume = "100"
 genesis_plus_gx_sms_fm_channel_6_volume = "100"
 genesis_plus_gx_sms_fm_channel_7_volume = "100"
 genesis_plus_gx_sms_fm_channel_8_volume = "100"
-genesis_plus_gx_sound_output = "stereo"
+genesis_plus_gx_sound_output = "mono"
 genesis_plus_gx_system_bram = "per bios"
 genesis_plus_gx_system_hw = "auto"
 genesis_plus_gx_ym2413 = "auto"