[LAD] jack clicks with no xruns

Hi all, Does anyone else get clicks which occur continuously after getting a single xrun in jack? (i.e no further xruns are reported, but the audio is crackling). I'm setting up an art installation which has to run for hours on end without intervention, and this seems to be happening after some time (running jack in realtime mode). I'm using a stock kernel in OpenSuse - would it help to use a lowlatency one? The audio doesn't need lowlat - I'm using a buffer size of 1024. I don't care about the odd xrun - as long as the audio goes back to normal afterwards, any help gratefully received. This is running in my own software so there is more than a chance it's something I'm doing wrong. cheers, dave