diff --git a/server/szurubooru/api/post_api.py b/server/szurubooru/api/post_api.py
index aaa7437..58d0708 100644
--- a/server/szurubooru/api/post_api.py
+++ b/server/szurubooru/api/post_api.py
@@ -65,6 +65,7 @@ def create_post(
     posts.update_post_relations(post, relations)
     posts.update_post_notes(post, notes)
     posts.update_post_flags(post, flags)
+    posts.test_sound(post, content)
     if ctx.has_file('thumbnail'):
         posts.update_post_thumbnail(post, ctx.get_file('thumbnail'))
     ctx.session.add(post)
diff --git a/server/szurubooru/func/images.py b/server/szurubooru/func/images.py
index b3df55e..4dce5d8 100644
--- a/server/szurubooru/func/images.py
+++ b/server/szurubooru/func/images.py
@@ -4,6 +4,7 @@ import json
 import shlex
 import subprocess
 import math
+import re
 from szurubooru import errors
 from szurubooru.func import mime, util
 
@@ -141,17 +142,43 @@ class Image:
             with open(mp4_temp_path, 'rb') as mp4_temp:
                 return mp4_temp.read()
 
+    def check_for_sound(self) -> bool:
+        audioinfo = json.loads(self._execute([
+            '-i', '{path}',
+            '-of', 'json',
+            '-select_streams', 'a',
+            '-show_streams',
+        ], program='ffprobe').decode('utf-8'))
+        assert 'streams' in audioinfo
+        if len(audioinfo['streams']) < 1:
+            return False
+
+        log = self._execute([
+            '-i', '{path}',
+            '-af', 'volumedetect',
+            '-f', 'null',
+            '-y', '/dev/null',
+        ], get_logs=True).decode('utf-8')
+        log_match = re.search(r'.*volumedetect.*mean_volume: (.*) dB', log)
+        assert log_match
+        assert log_match.groups()
+        meanvol = float(log_match.groups()[0])
+
+        # -91.0 dB is the minimum for 16-bit audio, assume sound if > -80.0 dB
+        return meanvol > -80.0
+
     def _execute(
             self,
             cli: List[str],
             program: str = 'ffmpeg',
-            ignore_error_if_data: bool = False) -> bytes:
+            ignore_error_if_data: bool = False,
+            get_logs: bool = False) -> bytes:
         extension = mime.get_extension(mime.get_mime_type(self.content))
         assert extension
         with util.create_temp_file(suffix='.' + extension) as handle:
             handle.write(self.content)
             handle.flush()
-            cli = [program, '-loglevel', '24'] + cli
+            cli = [program, '-loglevel', '32' if get_logs else '24'] + cli
             cli = [part.format(path=handle.name) for part in cli]
             proc = subprocess.Popen(
                 cli,
@@ -169,7 +196,7 @@ class Image:
                     raise errors.ProcessingError(
                         'Error while processing image.\n'
                         + err.decode('utf-8'))
-            return out
+            return err if get_logs else out
 
     def _reload_info(self) -> None:
         self.info = json.loads(self._execute([
diff --git a/server/szurubooru/func/posts.py b/server/szurubooru/func/posts.py
index a10780c..97a69f8 100644
--- a/server/szurubooru/func/posts.py
+++ b/server/szurubooru/func/posts.py
@@ -474,6 +474,17 @@ def generate_alternate_formats(post: model.Post, content: bytes) \
     return new_posts
 
 
+def test_sound(post: model.Post, content: bytes) -> None:
+    assert post
+    assert content
+    if mime.is_video(mime.get_mime_type(content)):
+        if images.Image(content).check_for_sound():
+            flags = [x for x in post.flags.split(',') if x]
+            if model.Post.FLAG_SOUND not in flags:
+                flags.append(model.Post.FLAG_SOUND)
+            update_post_flags(post, flags)
+
+
 def update_post_content(post: model.Post, content: Optional[bytes]) -> None:
     assert post
     if not content: