JP15 Output Issue?

I recently bought a teal quilt top JP15 and love the guitar, but I noticed there’s a little bit of signal leaking through when I have the switches set to magnetic pickups, the magnetic pickup volume all the way down, and the piezo volume turned up. The signal goes away completely once I turn the piezo volume down all the way. Does that happen with all JP15s, or does mine have an issue?

Thanks!