diff --git a/targets/mega65/configdb.c b/targets/mega65/configdb.c
index a6a6f131..7743112f 100644
--- a/targets/mega65/configdb.c
+++ b/targets/mega65/configdb.c
@@ -86,6 +86,7 @@ static const struct xemutools_configdef_switch_st switch_options[] = {
 	{ "besure", "Skip asking \"are you sure?\" on RESET or EXIT", &i_am_sure_override },
 	{ "skipunhandledmem", "Do not even ask on unhandled memory access (hides problems!!)", &configdb.skip_unhandled_mem },
 	{ "fullborders", "Show non-clipped display borders", &configdb.fullborders },
+	{ "nosound", "Disables audio emulation", &configdb.nosound },
 	{ NULL }
 };
 
diff --git a/targets/mega65/configdb.h b/targets/mega65/configdb.h
index 65f26c5f..96785c1b 100644
--- a/targets/mega65/configdb.h
+++ b/targets/mega65/configdb.h
@@ -86,6 +86,7 @@ struct configdb_st {
 	int	stereoseparation;
 	int	mastervolume;
 	double	fast_mhz;
+	int	nosound;
 };
 
 extern struct configdb_st configdb;
diff --git a/targets/mega65/mega65.c b/targets/mega65/mega65.c
index 9be27115..4684f52e 100644
--- a/targets/mega65/mega65.c
+++ b/targets/mega65/mega65.c
@@ -814,7 +814,7 @@ int main ( int argc, char **argv )
 	} else if (configdb.autoload)
 		c64_register_fake_typing(fake_typing_for_load65);
 #endif
-	if (audio) {
+	if (audio && !configdb.nosound) {
 		DEBUGPRINT("AUDIO: start" NL);
 		SDL_PauseAudioDevice(audio, 0);
 	}
diff --git a/xemu/sid.c b/xemu/sid.c
index e0d513f2..f7eaf906 100644
--- a/xemu/sid.c
+++ b/xemu/sid.c
@@ -658,26 +658,25 @@ void sid_init ( struct SidEmulation *sidemu, unsigned long cyclesPerSec, unsigne
 	// SID emulation (we only have a SID snapshot every 20ms to work with) during rendering our computing
 	// granularity then is 'one sample' (not 'one cpu cycle' - but around 20).. instead of still trying to simulate a
 	// 15-bit cycle-counter we may directly use a sample-counter instead (which also reduces rounding issues).
-	int i;
 #ifdef SID_USES_SAMPLE_ENV_COUNTER
 	sidemu->limit_LFSR = round(((float)0x8000)/sidemu->cyclesPerSample);	// original counter was 15-bit
-	for (i=0; i<16; i++) {
+	for (int i=0; i<16; i++) {
 		// counter must reach respective threshold before envelope value is incremented/decremented
 		sidemu->envelope_counter_period[i]= (int)round((float)(attackTimes[i]*cyclesPerSec)/1000/256/cyclesPerSample)+1;	// in samples
 		sidemu->envelope_counter_period_clck[i]= (int)round((float)(attackTimes[i]*cyclesPerSec)/1000/256)+1;				// in clocks
 	}
 #else
 	sidemu->limit_LFSR = 0x8000;	// counter 15-bit
-	for (i=0;i<16;i++) {
+	for (int i=0; i<16; i++) {
 		// counter must reach respective threshold before envelope value is incremented/decremented
 		sidemu->envelope_counter_period[i]=      (int)floor((float)(attackTimes[i]*cyclesPerSec)/1000/256)+1;	// in samples
 		sidemu->envelope_counter_period_clck[i]= (int)floor((float)(attackTimes[i]*cyclesPerSec)/1000/256)+1;	// in clocks
 	}
 #endif
 	// lookup table for decay rates
-	unsigned char from[] =  {93, 54, 26, 14,  6,  0};
-	unsigned char val[] = { 1,  2,  4,  8, 16, 30};
-	for (i= 0; i<256; i++) {
+	static const unsigned char from[] =  {93, 54, 26, 14,  6,  0};
+	static const unsigned char val[] = { 1,  2,  4,  8, 16, 30};
+	for (int i = 0; i<256; i++) {
 		unsigned char v= 1;
 		unsigned char j;
 		for (j= 0; j<6; j++) {