To use Reflectix (that shiny insulation sheet stuff with the little bubbles in between) under my ball pythons tub?

I put it on there last night thinking it was fine, and this morning I went to check on him and noticed my piece of 11" flexwatt was buzzing pretty loud. It sounds very electrical when I put my ear up to it. I don't know if this was there before and I just didn't notice or what.

He is still on a lamp dimmer, but I finally got fed up with it and its fluctuations, so his thermostat should be arriving in the mail in a couple days.

I searched threads and it said sometimes with a dimmer the buzzing happens.

I quickly wrapped the connections in electrical tape this morning.

The buzzing is not safe I am guessing?

I touched the connections and pad and did not feel an electrical current of any kind.

Thanks for any and all help, this worries me!
Sara