Hi *all,
if you own a Dunlop x Mini Pedal and are "afraid" of sticking velco to that smooth and clean rubber surface - first because: we don't do so and second: it might not stick as desired - simply switch the metal plate around and stick the velcro to the metal side. 
I do not know if this is an insulation / radiation blocking issue, if you use it as a standard volume pedal, but as an expression pedal this should not make any difference (in regards of noise or hum).
cheers
Stefan