Got HTPC running again and did some testing. Seeking doesn't mess sync up anymore. BUT offset depends on codec. Found out that MPV and Purevideo displayed teletext-subs 500ms late and PowerDVD 7 SP displayed subs about 2 sec early.
When you look at the clip on VLC, timing is perfect but there are other issues like other language subs flashing briefly when new subs get displayed. So there could be something wrong on that providers way of delivering subs too.. Too bad standards aren't followed that strictly.
When you look at the clip on VLC, timing is perfect but there are other issues like other language subs flashing briefly when new subs get displayed. So there could be something wrong on that providers way of delivering subs too.. Too bad standards aren't followed that strictly.