diff --git a/src/devices/sound/qsoundhle.h b/src/devices/sound/qsoundhle.h
index 9ede58699d2..dfaded4d4bc 100644
--- a/src/devices/sound/qsoundhle.h
+++ b/src/devices/sound/qsoundhle.h
@@ -167,9 +167,6 @@ private:
 
 	// sub functions
 	int16_t read_sample(uint16_t bank, uint16_t address);
-
-	inline int16_t pcm_update(struct qsound_voice *v, int32_t *echo_out);
-	inline void adpcm_update(int voice_no, int nibble);
 };
 
 DECLARE_DEVICE_TYPE(QSOUND_HLE, qsound_hle_device)