diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c
index 1179b39a30..e5208fc2bf 100644
--- a/libavcodec/alsdec.c
+++ b/libavcodec/alsdec.c
@@ -770,7 +770,7 @@ static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
         int          delta[8];
         unsigned int k    [8];
         unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
-        unsigned int i;
+        unsigned int i = start;
 
         // read most significant bits
         unsigned int high;
@@ -781,7 +781,7 @@ static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
 
         current_res = bd->raw_samples + start;
 
-        for (sb = 0; sb < sub_blocks; sb++) {
+        for (sb = 0; sb < sub_blocks; sb++, i = 0) {
             k    [sb] = s[sb] > b ? s[sb] - b : 0;
             delta[sb] = 5 - s[sb] + k[sb];