Well i don't have any antennae mods... and MJ works in other vessels etc. It seems sporadic and not very clear when it works and when it doesn't. I am having 100% failure during a launch lately. It starts out fine, gets to 'coasting to edge of atmos' then turns for circularize burn and then nothing... auto warp does not kick in again and the ship sails past the node and just crashes to the ground without ever burning. I can, and do turn off the AP and burn manually to get into orbit... fine. But that sort of not the point... I 'can' launch to orbit and rendezvous and all that manually, but like MJ to skip the routine bits. I just updated every mod I have with a freshly downloaded version even if it wasn't needed... they were all up to date. And still same issue. one last thing - occasionally, the mechjeb unit will explode on the launch pad as soon as physics kicks in... very strange to see... not always, so hard to say why. But it used to be funny... not any more