I'd go with cable connection - probably more than likely (the 15 mins it warms up and something there after is loosened or expands and then connection broken
my Alpine gets "
" warm after only 10 to 15 mins of usage, mainly due (I guess) to the lack of decent ventilation in the back of that center console.
Other option - which is what I intend on doing, (prior to the boot build) will be to run seperate power to the head and pre-amp booster box and to the power cap (prior to finally hitting the AMP).
R00