Are DC converters adjustable?

[alien_scones]

Are DC converters adjustable?

I suspect the DC voltage is a little on the high side.

I don't have a multimeter yet.

I have started to swap out the incandescent lights with warm LEDs.

After replacing the lights, I noticed that the warm LEDs quickly turn into the colder bright blue-white 10K spectrum, and minutes after that they begin to diminish in brightness and emit smoke. The LED lights are uncharacteristically very hot to the touch, and in some cases cause the attached backing tape to melt.

Some of the fixtures look like the previous incandescent lamps burned a little on the hot side.

It's on all the fixtures so far that I've replaced.

Should I be planning on replacing the converter or is there a quick adjustment I can make? Or is a bad battery causing this?

This is for a Thor 2001 Citation bumper pull 26S.

Thanks