Overbridge Digitone in Logic

Ive been fiddling about with getting Overbridge to work in Logic. I can set it up ok.

Set Audio Input to Digitone Bit Accurate in prefs
Add Digitone plugin as Software Instrument with 6 stereo outputs
Create 4 setero audio tracks 3-4, 5-6, 7-8, 9-10

Hit play in the Logic Transport …great it all works
Stop play back and the hit play again…silence no sound is being produced although you can see the audio meters on each audio track are regestering a sounds.

Switch of the Clock and Sync in the plugin and press play on the Digitone and sound is back

EDIT Got that wrong the sound Im geeting initially is from the plugin not the audio tracks . Not getting any sound at all from the audio tracks when the plugin is loaded and passing sync and clock info.