Overheating switch

Just recently while driving along my head/side light switch started to smoke and was red hot to touch after driving with the lights on at night for about half an hour. The switch was ruined but was old so I bought a new one and started again. Same thing happened! This all happened after I bought a pair of new side light and Indicator lenses with mountings for the front from Paddocks. The manufacturer was Wipac so not a cheap version. Every time I open the lens I find one of the bulbs is popping out of the seatings which isn't suprising as the 2 seating lugs on the bulbs seem very shallow and its a job to keep them in there. Would that cause them to short and cause the switch to burn? If so any advice and has anyone else had this problem? Since the second switch burnt I bought another but am only running the headlights and interior instrument light off it with no problem at all. The front side lights are disconnected but be nice to be able to use them again? Perhaps there are bulbs with bigger fitting lugs? Help?

Sounds like your new holders are faulty send them back

Agree, bulbs should be a firm fit to keep good contact or they either fall out or will flicker with engine / road vibes.
Why didnt your fuse pop? check its the right rating.

Fuse?

Check that you are using the correct 5 watt side light bulbs. I have seen a lot of people put 21 watt bulbs in, an instant overload to the circuit and an MOT fail.

Will check all these thank you. The fuse is correct and has never blown. Weird

There is no fuse in the sidelight circuit of a S3 - it's straight off the switch. As is quite a lot more..... Be careful in there.