I tried to look at the old subtitle plugin and how it was done there but couldn't see how to apply that to the subtitle handling that vdr does.
I suppose you're talking about dvb subtitles. Per chance, are you seeing the problem on ITV3 (Eurobird 1/Astra 2)?
Yes, I am talking about the dvb subtitles. Here the subtitles are in sync when watching live. But when I try to watch a recording I get the subtitles 6 seconds too early. If I understood it correctly the reason for this is known. This explains the reason: http://www.linuxtv.org/pipermail/vdr/2008-October/018072.html but not the cure :)
Regards,
Josce