I have measured today surface temperature of my PWR-Line AP and I got44,5°C(room temp ~ 22°C) That seems to be quite high to me. Are you considering some power optimizations for next revision of the HW?
I have been pulling my hair over the Pwr-line units I have recently purchased. 6.48 indeed breaks pwr-line communication completely. Installing long-term 6.46.8 solved the issue.