Electro Harmonix Deluxe Bass Big Muff Pi

i had been after this pedal for ages so i was delighted when i finally got it.
after trying it out i found that it worked fine when operating the bypass switch and gave some great sounds using the blend tone and sustain switches, but when the crossover switch was pressed it became the worst pedal i have had the misfortune to own. the amount of interference and static this produced was unacceptable and when balanced out with the gate switch caused the sound to drop in and out. no matter how long i spent making adjustments this problem remained and even became worse the longer that the pedal was in use. this noise was even worse and a high pitch humming was added when the pedal was connected to a 9v power supply and not run directly off the battery. after 3 days of trying to get a decent sound when using the crossover switch i have given up and i have had to return this pedal as faulty.
when the replacement pedal comes hopefully i will edit this review to reflect what should be a top quality pedal and it was just unlucky that i was unfortunate to have received a one off faulty unit.