srt subs timing change

[sambat]

Am having a problem syncing up a sub to a TV episode.
The subs seem to be ~11 seconds late coming up.
SubSync can't get the srt and video aligned, but before I try other methods (subedit etc), I was wondering if anyone ever came across a way of subtracting a constant amount e.g 't=00:00:11,000' from the listed times in a srt file to get it into the ballpark so that SubSync has a better shot at it.
As I say, it's only a question posed before I look at the more conventional fixes.
Thanks for any comments.

3
00:01:41,384 --> 00:01:42,810
- Afternoon, Doug. - Hey.

4
00:01:42,914 --> 00:01:43,992
What are you doing here?

[locotus]

Subtitle Edit > synchronization > adjust all times (earlier/later)