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diff --git a/firmware/pcm.c b/firmware/pcm.c
index 94b0d6e..9e2b900 100644
--- a/firmware/pcm.c
+++ b/firmware/pcm.c
@@ -258,6 +258,21 @@ bool pcm_is_initialized(void)
     return pcm_is_ready;
 }
 
+static inline int32_t FRACMUL(int32_t x, int32_t y)
+{
+    return (int32_t) (((int64_t)x * y) >> 31);
+}
+
+static inline void pcm_apply_gain(const void *addr, size_t s)
+{
+    int16_t *pcm = (int16_t *)addr; /* cast away constness, yay */
+    int32_t gain = 0x7fffffff>>5;
+    for (unsigned i = 0; i < s/2; i++)
+    {
+        pcm[i] = FRACMUL(pcm[i], gain);
+    }
+}
+
 /* Common code to pcm_play_data and pcm_play_pause */
 static void pcm_play_data_start(const void *addr, size_t size)
 {
@@ -281,6 +296,7 @@ static void pcm_play_data_start(const void *addr, size_t size)
     {
         logf(" pcm_play_dma_start");
         pcm_apply_settings();
+        pcm_apply_gain(addr, size);
         pcm_play_dma_start(addr, size);
         pcm_playing = true;
         pcm_paused = false;
@@ -327,9 +343,11 @@ bool pcm_play_dma_complete_callback(enum pcm_dma_status status,
         /* Call registered callback to obtain next buffer */
         get_more(addr, size);
         ALIGN_AUDIOBUF(*addr, *size);
-
         if (*addr && *size)
+        {
+            pcm_apply_gain(*addr, *size);
             return true;
+        }
     } 
 
     /* Error, callback missing or no more DMA to do */