command spacebar not working on SOME sessions on Pro Tools 11

Hi, I am running PT 11 on a mac mini (Yosemite). My older sessions that I started in PT 10 are working fine but my new PT11 sessions (I use a template I created in PT 10) won't let me go into record with 'command spacebar) this rules out trashing prefs,disabling Spotlight and anything non PT related as some sessions work fine. All the PT prefs in 'operation' are the same too.. can you help??