Problems with parts exploding on the launchpad

[Armarnis]

hi there, i have a problem that some parts (octagonal struts, batteries, wedge holders from universal storage) explode as soon as i go from the vab to the landing pad with my shiny new rocket :S

i use some mods:

boxsat

contract configurator

various contract packs

dmagic orbital science

FAR

KAS

KIS

Infernal Robotics

procedural fairings

remote tech

scan sat

stage recovery

universal storage

i wonder if there is any explicit reason to this cause it happens no matter if the part is directly exposed, behind a fairing or anything else, i havent even launched my rocket...

in some thread i found a workaround by editing the part and adding the line

thermalMassModifier = 5000

to it (the 5000 is made up by me cause i dont enjoy rockets exploding because of 1 connecting part so i thought "higher the better").

has someone an idea or knows why the parts go boom?

[Kryxal]

Why does the F3 screen SAY they're going boom?

[Armarnis]

overheating