rosegarden/jack latency issue

[hanzf]

Hello,

Trying out Rosegarden, I have a problem with latency (at least I think that’s what it is).
When I record some audio tracks, they are about 70..100 ms out of time, related to each other.
With Ardour, I don’t have this problem - here the sync inaccuracy between the tracks is about 2..3 ms.
I’d like to use Rosegarden because it combines audio recording and sequencer functionality, but how can I get the audio tracks to be properly in time?
(I always had this problem in Windows and I found a way to correct it manually after recording but it’s much better when it just works.
The bootup menu says my system is "low latency".

Thank you

Hans