Stuttering video

Since upgrading to the latest version of atvflash, my ripped DVD collection is unwatchable. The DVDs are Vob files/ts folder, and previousely played perfectly, now they stutter very badly. Tech support has failed, any ideas?
I have already reinstalled etc

If the AppleTV system software was recently updated you will want to re-run the Smart Installer:

Thanks, but have tried running the smart installer (several times). The problem seems to be specific to ts/vow files