diff --git a/supysonic/api/__init__.py b/supysonic/api/__init__.py
index 04e9b5c..d0104ad 100644
--- a/supysonic/api/__init__.py
+++ b/supysonic/api/__init__.py
@@ -231,16 +231,13 @@ def get_entity(req, cls, param = 'id'):
 
     try:
         eid = uuid.UUID(eid)
-    except:
-        return False, req.error_formatter(0, 'Invalid %s id' % cls.__name__)
-
-    try:
         entity = cls[eid]
+        return True, entity
+    except ValueError:
+        return False, req.error_formatter(0, 'Invalid %s id' % cls.__name__)
     except ObjectNotFound:
         return False, (req.error_formatter(70, '%s not found' % cls.__name__), 404)
 
-    return True, entity
-
 from .system import *
 from .browse import *
 from .user import *
diff --git a/supysonic/api/albums_songs.py b/supysonic/api/albums_songs.py
index 9ae4289..e54b5f6 100644
--- a/supysonic/api/albums_songs.py
+++ b/supysonic/api/albums_songs.py
@@ -39,7 +39,7 @@ def rand_songs():
         fromYear = int(fromYear) if fromYear else None
         toYear = int(toYear) if toYear else None
         fid = uuid.UUID(musicFolderId) if musicFolderId else None
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter format')
 
     query = Track.select()
@@ -71,7 +71,7 @@ def album_list():
     try:
         size = int(size) if size else 10
         offset = int(offset) if offset else 0
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter format')
 
     query = select(t.folder for t in Track)
@@ -114,7 +114,7 @@ def album_list_id3():
     try:
         size = int(size) if size else 10
         offset = int(offset) if offset else 0
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter format')
 
     query = Album.select()
diff --git a/supysonic/api/annotation.py b/supysonic/api/annotation.py
index 6f012c6..d6ebc9c 100644
--- a/supysonic/api/annotation.py
+++ b/supysonic/api/annotation.py
@@ -45,11 +45,9 @@ def try_star(cls, starred_cls, eid):
 
     try:
         uid = uuid.UUID(eid)
-    except:
-        return dict(code = 0, message = 'Invalid {} id {}'.format(cls.__name__, eid))
-
-    try:
         e = cls[uid]
+    except ValueError:
+        return dict(code = 0, message = 'Invalid {} id {}'.format(cls.__name__, eid))
     except ObjectNotFound:
         return dict(code = 70, message = 'Unknown {} id {}'.format(cls.__name__, eid))
 
@@ -73,7 +71,7 @@ def try_unstar(starred_cls, eid):
 
     try:
         uid = uuid.UUID(eid)
-    except:
+    except ValueError:
         return dict(code = 0, message = 'Invalid id {}'.format(eid))
 
     delete(s for s in starred_cls if s.user.id == request.user.id and s.starred.id == uid)
@@ -145,7 +143,7 @@ def rate():
     try:
         uid = uuid.UUID(id)
         rating = int(rating)
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter')
 
     if not 0 <= rating <= 5:
@@ -186,7 +184,7 @@ def scrobble():
     if t:
         try:
             t = int(t) / 1000
-        except:
+        except ValueError:
             return request.error_formatter(0, 'Invalid time value')
     else:
         t = int(time.time())
diff --git a/supysonic/api/browse.py b/supysonic/api/browse.py
index adddc71..150ef43 100644
--- a/supysonic/api/browse.py
+++ b/supysonic/api/browse.py
@@ -50,7 +50,7 @@ def list_indexes():
     if ifModifiedSince:
         try:
             ifModifiedSince = int(ifModifiedSince) / 1000
-        except:
+        except ValueError:
             return request.error_formatter(0, 'Invalid timestamp')
 
     if musicFolderId is None:
@@ -58,11 +58,9 @@ def list_indexes():
     else:
         try:
             mfid = uuid.UUID(musicFolderId)
-        except:
-            return request.error_formatter(0, 'Invalid id')
-
-        try:
             folder = Folder[mfid]
+        except ValueError:
+            return request.error_formatter(0, 'Invalid id')
         except ObjectNotFound:
             return request.error_formatter(70, 'Folder not found')
         if not folder.root:
diff --git a/supysonic/api/chat.py b/supysonic/api/chat.py
index 0fa4920..8e1421a 100644
--- a/supysonic/api/chat.py
+++ b/supysonic/api/chat.py
@@ -29,7 +29,7 @@ def get_chat():
     since = request.values.get('since')
     try:
         since = int(since) / 1000 if since else None
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter')
 
     with db_session:
diff --git a/supysonic/api/media.py b/supysonic/api/media.py
index 6af08e8..3203c53 100644
--- a/supysonic/api/media.py
+++ b/supysonic/api/media.py
@@ -70,7 +70,7 @@ def stream_media():
     if maxBitRate:
         try:
             maxBitRate = int(maxBitRate)
-        except:
+        except ValueError:
             return request.error_formatter(0, 'Invalid bitrate value')
 
         if dst_bitrate > maxBitRate and maxBitRate != 0:
@@ -100,7 +100,7 @@ def stream_media():
             else:
                 dec_proc = subprocess.Popen(decoder, stdout = subprocess.PIPE)
                 proc = subprocess.Popen(encoder, stdin = dec_proc.stdout, stdout = subprocess.PIPE)
-        except:
+        except OSError:
             return request.error_formatter(0, 'Error while running the transcoding process')
 
         def transcode():
@@ -155,7 +155,7 @@ def cover_art():
     if size:
         try:
             size = int(size)
-        except:
+        except ValueError:
             return request.error_formatter(0, 'Invalid size value')
     else:
         return send_file(os.path.join(res.path, 'cover.jpg'))
diff --git a/supysonic/api/playlists.py b/supysonic/api/playlists.py
index 17e997f..4d2fee6 100644
--- a/supysonic/api/playlists.py
+++ b/supysonic/api/playlists.py
@@ -70,7 +70,7 @@ def create_playlist():
     songs = request.values.getlist('songId')
     try:
         playlist_id = uuid.UUID(playlist_id) if playlist_id else None
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid playlist id')
 
     if playlist_id:
diff --git a/supysonic/api/search.py b/supysonic/api/search.py
index 847362a..9366a85 100644
--- a/supysonic/api/search.py
+++ b/supysonic/api/search.py
@@ -33,7 +33,7 @@ def old_search():
         count = int(count) if count else 20
         offset = int(offset) if offset else 0
         newer_than = int(newer_than) / 1000 if newer_than else 0
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter')
 
     min_date = datetime.fromtimestamp(newer_than)
@@ -82,7 +82,7 @@ def new_search():
         album_offset =  int(album_offset)  if album_offset  else 0
         song_count =    int(song_count)    if song_count    else 20
         song_offset =   int(song_offset)   if song_offset   else 0
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter')
 
     if not query:
@@ -111,7 +111,7 @@ def search_id3():
         album_offset =  int(album_offset)  if album_offset  else 0
         song_count =    int(song_count)    if song_count    else 20
         song_offset =   int(song_offset)   if song_offset   else 0
-    except:
+    except ValueError:
         return request.error_formatter(0, 'Invalid parameter')
 
     if not query:
diff --git a/supysonic/db.py b/supysonic/db.py
index 019524c..2ceebf2 100644
--- a/supysonic/db.py
+++ b/supysonic/db.py
@@ -404,7 +404,7 @@ class Playlist(db.Entity):
                 tid = UUID(t)
                 track = Track[tid]
                 tracks.append(track)
-            except:
+            except (ValueError, ObjectNotFound):
                 should_fix = True
 
         if should_fix:
diff --git a/supysonic/frontend/playlist.py b/supysonic/frontend/playlist.py
index d3f62d2..1e7d8ad 100644
--- a/supysonic/frontend/playlist.py
+++ b/supysonic/frontend/playlist.py
@@ -39,7 +39,7 @@ def playlist_index():
 def playlist_details(uid):
     try:
         uid = uuid.UUID(uid)
-    except:
+    except ValueError:
         flash('Invalid playlist id')
         return redirect(url_for('playlist_index'))
 
@@ -56,7 +56,7 @@ def playlist_details(uid):
 def playlist_update(uid):
     try:
         uid = uuid.UUID(uid)
-    except:
+    except ValueError:
         flash('Invalid playlist id')
         return redirect(url_for('playlist_index'))
 
@@ -75,14 +75,14 @@ def playlist_update(uid):
         playlist.public = request.form.get('public') in (True, 'True', 1, '1', 'on', 'checked')
         flash('Playlist updated.')
 
-    return playlist_details(uid)
+    return playlist_details(str(uid))
 
 @app.route('/playlist/del/<uid>')
 @db_session
 def playlist_delete(uid):
     try:
         uid = uuid.UUID(uid)
-    except:
+    except ValueError:
         flash('Invalid playlist id')
         return redirect(url_for('playlist_index'))
 
diff --git a/supysonic/managers/folder.py b/supysonic/managers/folder.py
index d4027ba..8cd89bb 100644
--- a/supysonic/managers/folder.py
+++ b/supysonic/managers/folder.py
@@ -43,7 +43,7 @@ class FolderManager:
         if isinstance(uid, strtype):
             try:
                 uid = uuid.UUID(uid)
-            except:
+            except ValueError:
                 return FolderManager.INVALID_ID, None
         elif isinstance(uid, uuid.UUID):
             pass
diff --git a/supysonic/managers/user.py b/supysonic/managers/user.py
index 1eac546..2931eef 100644
--- a/supysonic/managers/user.py
+++ b/supysonic/managers/user.py
@@ -35,7 +35,7 @@ class UserManager:
         if isinstance(uid, strtype):
             try:
                 uid = uuid.UUID(uid)
-            except:
+            except ValueError:
                 return UserManager.INVALID_ID, None
         elif isinstance(uid, uuid.UUID):
             pass
diff --git a/supysonic/scanner.py b/supysonic/scanner.py
index e3cef28..f6dfcfd 100644
--- a/supysonic/scanner.py
+++ b/supysonic/scanner.py
@@ -310,7 +310,7 @@ class Scanner:
             if transform:
                 value = transform(value)
                 return value if value else default
-        except:
+        except KeyError:
             return default
 
     def stats(self):
diff --git a/supysonic/watcher.py b/supysonic/watcher.py
index a772261..a605d4b 100644
--- a/supysonic/watcher.py
+++ b/supysonic/watcher.py
@@ -246,7 +246,7 @@ class SupysonicWatcher(object):
         try:
             signal(SIGTERM, self.__terminate)
             signal(SIGINT, self.__terminate)
-        except:
+        except ValueError:
             logger.warning('Unable to set signal handlers')
 
         queue.start()