Hi - My PV2 has flown perfectly, from out of the box til recently, when I left it home alone while I was out of the country for a month (wishing I had it with me!). When I returned, I ensured everything was fully charged, did a pre-flight check, took it out for a morning's flight…and it kept plopping to one side (left) on take-off, even when adding a bit of power to counteract. This morning, with thanks to Pull_Up, I installed the new Mac upgrade via the Assistant (including the TX; calibrated IMU), went outside…and now it flops backwards :-( According to the Assistant, I have the latest upgrades now. Do I need to plug the USB directly into the TX board? The Assistant showed the TX upgrade to have worked fine. I'm very sad that my PV2 is now so confused! Ideas? Thank-you!