WTL Simplex II>A23 Interconnect>& Rogue Audio Cronus Magnum II Hum

Hello All,

First post, apologies in advance for poor etiquette. My (new) WTL Simplex II has been causing me some annoyance with a persistent audible hum, presumably, a ground loop. I’ve done all of the usual isolation maneuvers to no avail. That is, until now! I touched the ground lug and the right and left A23 interconnects and the hum dissipated significantly. When I touched the ground lug and the actual right and left channels plugs on the TT the hum seemed to all but disappear. Not sure what my next move is - grounding the ground lug to the right and left channel plugs seem daft! Any advice here would be appreciated. 

My system (analogue chain) is as follows:

WTL Simplex II>Auditorium 23 interconnects (parallel-symmetrical design with the shielded plugs in amp)>Rogue Audio Cronus Magnum II integrated amp.

Note: I’ve tried both London Decca Super Gold and a Clear Audio Arum Classic Mk II Wood cartridges and both hum.