Fix handling of unknown output from MPlayer

pymplb.py

@@ -141,7 +141,7 @@ def cmd(name, argtypes, obligatory, player, *args, **kwargs):
 					try:
 						argtypes = [cls._arg_types[y] for y in [x.strip('[]') for x in args]]
 					except KeyError:  # Unknown argument type
-						pass # Some garbage on the output (version?)
+						continue # Some garbage on the output (version?)
 
 				method = partial(cmd, name, argtypes, obligatory)
 				if len(args) == 0: