I have to run 2 x 4mm x 4 core surfix cable in parallell ... one cable is getting warm ... taking into consideration the distance and load (sometimes at 80-90 % full load).

Here the problem trying to roll the cable out straight ... I normally put the cable on the floor and roll it from the outside ... then just work the cable until it is straight ... it seems ther eis a problem with the surfix being supplied by certain companies ... for some reason the cable will not lay flat ... we have tried everything to straighten it ... in one part the cable has a terrible kink which has straightened as best we can ... my concern is running the cable in parrallel ... what effect does that kink have in the magnetic field ... should I be concerned?