Noise issue with my Hunter Hayes

Hey all, I’m having a problem with my EBMM H.H. model. If i lightly touch the strings I get a little pop. When I touch the bridge with one hand and do the same it does not happen.
Any ideas what may be causing this? It also does not do it with a Sterling axis that I have. The Sterling has humbuckers. The H.H. is sss with Piezo. But the problem happens when I’m plugged into either output jack.