diff --git a/src/driver.h b/src/driver.h
index 8c2cda3..b17376c 100644
--- a/src/driver.h
+++ b/src/driver.h
@@ -160,6 +160,7 @@ void FCEUI_CheatSearchShowExcluded(void);
 void FCEUI_CheatSearchSetCurrentAsOriginal(void);
 
 void FCEUI_SetLowPass(int q);
+void FCEUI_RemoveTriangleNoise(int d);
 
 void FCEUI_NSFSetVis(int mode);
 int FCEUI_NSFChange(int amount);
diff --git a/src/drivers/libretro/libretro.c b/src/drivers/libretro/libretro.c
index 96dece6..efeb8d8 100644
--- a/src/drivers/libretro/libretro.c
+++ b/src/drivers/libretro/libretro.c
@@ -1569,10 +1569,11 @@ static bool update_option_visibility(void)
          struct retro_core_option_display option_display;
          unsigned i;
          unsigned size;
-         char options_list[][25] = {
+         char options_list[][32] = {
             "fceumm_sndvolume",
             "fceumm_sndquality",
             "fceumm_sndlowpass",
+            "fceumm_removetrianglenoise",
             "fceumm_sndstereodelay",
             "fceumm_swapduty",
             "fceumm_apu_1",
@@ -2391,6 +2392,14 @@ static void check_variables(bool startup)
       FCEUI_SetLowPass(lowpass);
    }
 
+   var.key = "fceumm_removetrianglenoise";
+
+   if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
+   {
+      int newval = (!strcmp(var.value, "enabled")) ? 1 : 0;
+      FCEUI_RemoveTriangleNoise(newval);
+   }
+
    var.key = "fceumm_sndstereodelay";
 
    if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
diff --git a/src/drivers/libretro/libretro_core_options.h b/src/drivers/libretro/libretro_core_options.h
index a324d92..ffceb68 100644
--- a/src/drivers/libretro/libretro_core_options.h
+++ b/src/drivers/libretro/libretro_core_options.h
@@ -321,6 +321,20 @@ struct retro_core_option_v2_definition option_defs[] = {
       },
       "disabled",
    },
+   {
+      "fceumm_removetrianglenoise",
+      "Reduce Triangle Channel Popping",
+      NULL,
+      "Mute the triangle channel when its period drops into the ultrasonic range (period <= 3, > ~12 kHz at NTSC).  Eliminates the audible popping some games (Castlevania II: Simon's Quest, Jackal, etc.) produce in High / Very High sound quality, where the DAC reconstruction filter would otherwise fold the ultrasonic content back into the audible range.  Low quality is unaffected (it already silences ultrasonic triangle output).",
+      NULL,
+      "audio",
+      {
+         { "disabled", NULL },
+         { "enabled",  NULL },
+         { NULL, NULL },
+      },
+      "disabled",
+   },
    {
       "fceumm_sndstereodelay",
       "Stereo Sound Effect",
diff --git a/src/fceu.h b/src/fceu.h
index 74c9026..4ee4f2d 100644
--- a/src/fceu.h
+++ b/src/fceu.h
@@ -94,6 +94,16 @@ typedef struct {
 	uint32_t SndRate;
 	int soundq;
 	int lowpass;
+	int RemoveTriangleNoise;	/* Mute triangle channel when its period
+	                             * is low enough to produce only ultrasonic
+	                             * output (period <= 3, > ~12 kHz at NTSC),
+	                             * which the DAC reconstruction filter
+	                             * folds back as audible popping in HQ
+	                             * mode.  LQ already silences these
+	                             * unconditionally; this option mirrors
+	                             * that behaviour in HQ.  Default off to
+	                             * preserve existing HQ output bit-exactly
+	                             * when the option is not set. */
 } FCEUS;
 
 extern FCEUS FSettings;
diff --git a/src/sound.c b/src/sound.c
index e1c6438..97ffbd7 100644
--- a/src/sound.c
+++ b/src/sound.c
@@ -733,10 +733,21 @@ static void RDoSQLQ(void) {
 static void RDoTriangle(void) {
 	uint32_t V;
 	int32_t tcout = (tristep & 0xF);
+	uint32_t triangle_raw_period = (PSG[0xa] | ((PSG[0xb] & 7) << 8));
 	if (!(tristep & 0x10)) tcout ^= 0xF;
 	tcout = (tcout * 3) << 16;	/* (tcout<<1); */
 
-	if (!lengthcount[2] || !TriCount) {	/* Counter is halted, but we still need to output. */
+	/* The LQ tri/noise/PCM mixer (RDoTriangleNoisePCMLQ below) already
+	 * forces the triangle channel quiet when its period is low enough
+	 * to produce only ultrasonic output - games like Castlevania II
+	 * and Jackal repeatedly drop the triangle into that range when
+	 * they want silence, and without the gate the DAC reconstruction
+	 * filter folds the high-frequency content back as audible
+	 * popping.  Mirror the gate in the HQ path, conditional on the
+	 * RemoveTriangleNoise option so the default HQ output stays
+	 * bit-exact with the original code unless the user opts in. */
+	if (!lengthcount[2] || !TriCount
+	    || (FSettings.RemoveTriangleNoise && triangle_raw_period <= 3)) {	/* Counter is halted, but we still need to output. */
 		int32_t *start = &WaveHi[ChannelBC[2]];
 		int32_t count = SOUNDTS - ChannelBC[2];
 		while (count--) {
@@ -1246,6 +1257,10 @@ void FCEUI_SetLowPass(int q) {
 	FSettings.lowpass = q;
 }
 
+void FCEUI_RemoveTriangleNoise(int d) {
+	FSettings.RemoveTriangleNoise = d ? 1 : 0;
+}
+
 void FCEUI_SetSoundQuality(int quality) {
 	FSettings.soundq = quality;
 	SetSoundVariables();