I have always thought 'cable looping' (over the volume antenna) to be a crude way of muting the EW. The problem of unwanted sound gets worse with the Wilco/TF upgrade board.
So, I fitted a mute switch today. A small toggle switch that works within a 6mm case hole. The action and location is forward and backward set between the aerial loop. This has had no effect on the unit's sound output. I have it set to be push the toggle away from me to mute and towards me to work normally.
I took the opportunity to change the recently installed unit-power-on LED too to a dual colour LED. This gives a green light for power on and in normal use and a red light to show it's muted. No light means the power is turned off (yes, I changed the on/off switch too) or you have forgotten to plug the power supply into the rear of the unit!!!
The pictures speak for themselves I think.
You can also see the modified volume antenna end location 'grommet' rather than the clunky fitting that normally is in place. Gives better response etc.