diff --git a/libaegisub/audio/provider_hd.cpp b/libaegisub/audio/provider_hd.cpp
index 2969b244a..e26404abc 100644
--- a/libaegisub/audio/provider_hd.cpp
+++ b/libaegisub/audio/provider_hd.cpp
@@ -38,7 +38,7 @@ class HDAudioProvider final : public AudioProviderWrapper {
 	void FillBuffer(void *buf, int64_t start, int64_t count) const override {
 		auto missing = std::min(count, start + count - decoded_samples);
 		if (missing > 0) {
-			memset(static_cast<int16_t*>(buf) + count - missing, 0, missing * bytes_per_sample);
+			memset(static_cast<int16_t*>(buf) + count - missing, 0, missing * bytes_per_sample * channels);
 			count -= missing;
 		}
 
@@ -69,7 +69,7 @@ public:
 			for (int64_t i = 0; i < num_samples; i += block) {
 				if (cancelled) break;
 				block = std::min(block, num_samples - i);
-				source->GetAudio(file.write(i * bytes_per_sample, block * bytes_per_sample), i, block);
+				source->GetAudio(file.write(i * bytes_per_sample * channels, block * bytes_per_sample * channels), i, block);
 				decoded_samples += block;
 			}
 		});