Whenever I use my F1-X (always in conjuction w/ my SF-2 superfilter and my Markbass- amp) I get these annoying & damaging electric, loud pops that overloads my amp. these sounds are independent of bass-choice(elan & epic), cables and grounding, &c. could the choice of voltage cause this problem? on the F1-X you can choose between 220V and 240V. we have 230V in sweden...what would you choose? best regards from sweden/ kristjan aunver