I had a similar problem and found out it was the fan
The ESC would normally run totally fine and would never really get very hot (7.5T speed passion 76/22), but on occasions my car would cut out with the same overheat flashing lights.
After fiddling around with it for a bit, I realised the fan was sticking due to dust build up. Having the fan plugged in and not turning is essentially like creating a short circuit, causing the ESC to overheat instantly.
I took the dodgy fan off for the rest of the meeting and then replaced it the following week and the ESC has been working perfectly ever since 5 months on
I was quick to think the ESC was faulty when in fact its overheat protection did its job and saved its life!!!