diff --git a/src/Performance.c b/src/Performance.c
index 54a24d0..d860b3d 100644
--- a/src/Performance.c
+++ b/src/Performance.c
@@ -585,6 +585,14 @@ static void DmPerformance_playPattern(DmPerformance* slf, DmPattern* pttn) {
 			int16_t start = curve.start_value;
 			int16_t end = curve.end_value;
 
+			// Some MIDI control curves have invalid ranges (e.g. -22000 to 127)
+			bool start_in_range = start >= 0 && start <= 127;
+			bool end_in_range = end >= 0 && end <= 127;
+			if (curve.event_type == DmCurveType_CONTROL_CHANGE && !(start_in_range && end_in_range)) {
+				Dm_report(DmLogLevel_DEBUG, "DmPerformance: Curve is out-of-range");
+				continue;
+			}
+
 			float prev_value = start;
 			// TODO(lmichaelis): Check whether this is actually correct!
 			for (uint32_t k = 0; k < (duration / DmInt_CURVE_SPACING); ++k) {
diff --git a/src/Synth.c b/src/Synth.c
index e309745..cbd4f8a 100644
--- a/src/Synth.c
+++ b/src/Synth.c
@@ -241,10 +241,17 @@ size_t DmSynth_render(DmSynth* slf, void* buf, size_t len, DmRenderOptions fmt)
 			tsf_set_output(slf->channels[i].synth, TSF_MONO, 44100, 0);
 		}
 
+		float vol = slf->channels[i].volume;
+		if (vol < 0) {
+			vol = 0;
+		} else if (vol > 1) {
+			vol = 1;
+		}
+
 		if (fmt & DmRender_FLOAT) {
-			tsf_render_float(slf->channels[i].synth, buf, (int) len / channels, true, slf->channels[i].volume);
+			tsf_render_float(slf->channels[i].synth, buf, (int) len / channels, true, vol);
 		} else {
-			tsf_render_short(slf->channels[i].synth, buf, (int) len / channels, true, slf->channels[i].volume);
+			tsf_render_short(slf->channels[i].synth, buf, (int) len / channels, true, vol);
 		}
 	}