There is a huge difference between Epic X and first generation of Epic M in the cooling system regard.
With the Epic-X, I can record 8 to 12 minutes at fan speed 25% in normal room temperature before getting to the 42degrees and 100% fan blowing level.
Some times I change the fan level during take from 25 to 30%, wich is not allways the best for the sound department as they get a different sound noise level during take.
I also remarqued that there are different build and sound level of Epic-X at 25% setting.
The fan is my No 1 issue with this incredible camera. It's essencially a problem for the one who cares about a perfect sound.
I hope that the power management RED announced in future FW update will improve power consomption and therefore reduce the generated heat.