Hello, I own a Gretsch (G6118T-135) but I have a question... Are the pickups on my an anniversary known to make quite a lot of hum? I suspect I have a grounding issue - but - I just want to ask, just so I have not missed if these pickups are known to cause a huge hum. I use a Vox PF15R and get just about no electric hum or sound at all, when using my Gibson ES-335., a just a slight hum with my semi hollow 1997 Epiphone Les Paul Elite Florentine. When I plug in my Gretsch I instantly get a loud electric hum. It does not go away but get a lot lower in volume as soon as I touch the strings. I do own 2 identical Vox PF15Rs' and I get the exact same result with both amps, and in different rooms in my flat. Could this be caused by any other reason, other than a grounding issue? How to easiest check the guitar/inside the guitar for any grounding issue? Thx!