hello,
first , sorry my english..

i think i find my problem , i have two new quark125(just difference wire color).
i open one esc to remove alum and soft pad, top and bottom.
so i am try use Thermal adhesive the FET with alum panel, and adhesive to case.(just very very tight)
i am use 18cell Ni-Hm GP4300 battery and Feigao 7XL for testing,
i find FET heat very quickly transmission to case. and just great.
i comparison other esc heat not quick., and heat down as soon.

maybe soft pad not sticky all FET(i open found some).

i don't know i do this is right or wrong, hope this help.

Thank you.