diff --git a/libavcodec/mpegaudiodec_fixed.c b/libavcodec/mpegaudiodec_fixed.c
index 5ba1cc66fb..6fe372b38f 100644
--- a/libavcodec/mpegaudiodec_fixed.c
+++ b/libavcodec/mpegaudiodec_fixed.c
@@ -53,6 +53,7 @@ AVCodec ff_mp1_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
                                                       AV_SAMPLE_FMT_S16,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP2_DECODER
@@ -70,6 +71,7 @@ AVCodec ff_mp2_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
                                                       AV_SAMPLE_FMT_S16,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP3_DECODER
@@ -87,6 +89,7 @@ AVCodec ff_mp3_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
                                                       AV_SAMPLE_FMT_S16,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP3ADU_DECODER
@@ -104,6 +107,7 @@ AVCodec ff_mp3adu_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
                                                       AV_SAMPLE_FMT_S16,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP3ON4_DECODER
@@ -121,6 +125,6 @@ AVCodec ff_mp3on4_decoder = {
     .flush          = flush_mp3on4,
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
                                                       AV_SAMPLE_FMT_NONE },
-    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
 };
 #endif
diff --git a/libavcodec/mpegaudiodec_float.c b/libavcodec/mpegaudiodec_float.c
index 11cf7e6bf1..cdee337499 100644
--- a/libavcodec/mpegaudiodec_float.c
+++ b/libavcodec/mpegaudiodec_float.c
@@ -53,6 +53,7 @@ AVCodec ff_mp1float_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
                                                       AV_SAMPLE_FMT_FLT,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP2FLOAT_DECODER
@@ -70,6 +71,7 @@ AVCodec ff_mp2float_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
                                                       AV_SAMPLE_FMT_FLT,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP3FLOAT_DECODER
@@ -87,6 +89,7 @@ AVCodec ff_mp3float_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
                                                       AV_SAMPLE_FMT_FLT,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP3ADUFLOAT_DECODER
@@ -104,6 +107,7 @@ AVCodec ff_mp3adufloat_decoder = {
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
                                                       AV_SAMPLE_FMT_FLT,
                                                       AV_SAMPLE_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
 #if CONFIG_MP3ON4FLOAT_DECODER
@@ -121,6 +125,6 @@ AVCodec ff_mp3on4float_decoder = {
     .flush          = flush_mp3on4,
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
                                                       AV_SAMPLE_FMT_NONE },
-    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
 };
 #endif
diff --git a/libavcodec/mpegaudiodec_template.c b/libavcodec/mpegaudiodec_template.c
index b03f7cfc33..1faaa0ae52 100644
--- a/libavcodec/mpegaudiodec_template.c
+++ b/libavcodec/mpegaudiodec_template.c
@@ -30,6 +30,7 @@
 #include "libavutil/crc.h"
 #include "libavutil/float_dsp.h"
 #include "libavutil/libm.h"
+#include "libavutil/thread.h"
 #include "avcodec.h"
 #include "get_bits.h"
 #include "internal.h"
@@ -405,14 +406,9 @@ static av_cold void decode_init_static(void)
 
 static av_cold int decode_init(AVCodecContext * avctx)
 {
-    static int initialized_tables = 0;
+    static AVOnce init_static_once = AV_ONCE_INIT;
     MPADecodeContext *s = avctx->priv_data;
 
-    if (!initialized_tables) {
-        decode_init_static();
-        initialized_tables = 1;
-    }
-
     s->avctx = avctx;
 
 #if USE_FLOATS
@@ -438,6 +434,8 @@ static av_cold int decode_init(AVCodecContext * avctx)
     if (avctx->codec_id == AV_CODEC_ID_MP3ADU)
         s->adu_mode = 1;
 
+    ff_thread_once(&init_static_once, decode_init_static);
+
     return 0;
 }