Some comments from the gstreamer guys. They need your input. " It's hard to tell still. I wonder if wine uses some own gstreamer element. I could not find any traces of "quartz-src" in the gstreamer sources. The problem is visible in the last ~30 lines starting from here. Maybe you can ping the wine people again. This looks like an issue of how gstreamer is used to me. GST_PADS gstpad.c:3629:gst_pad_query:<'':quartz-src> [00m sending query 0x7a32bf40 typefind gsttypefindelement.c:930:gst_type_find_element_activate:<typefind> [00m Could not query upstream length! "