diff --git a/ffmpeg.c b/ffmpeg.c
index 37817ccef43468521c8a7a935107b4635b447345..a13dcf73f61790175ceea38b4d6a4abaa894ca9e 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -1624,7 +1624,7 @@ static void do_audio_out(AVFormatContext *s, OutputStream *ost,
                                           dec->channel_layout, dec->sample_fmt, dec->sample_rate,
                                           0, NULL);
             av_opt_set_int(ost->swr, "dither_method", ost->swr_dither_method,0);
-            av_opt_set_int(ost->swr, "dither_scale", ost->swr_dither_scale,0);
+            av_opt_set_double(ost->swr, "dither_scale", ost->swr_dither_scale,0);
             if (ost->audio_channels_mapped)
                 swr_set_channel_mapping(ost->swr, ost->audio_channels_map);
             av_opt_set_double(ost->swr, "rmvol", ost->rematrix_volume, 0);