JJ 100 Picking up Radio Broadcast

I have about a year on my power tubes and I was preparing to make the tube investment.

I just noticed the amp starting to pick up a radio broadcast.

Which set of tubes would pick up radio, the Power tubes or Pre-Amp Tubes?



Thanks?

Are you sure its not just dirty power? Are you using an isolated power supply with any pedals and an isolated power strip or conditioner? Pickup cavity shielded? Decent cables?