The statement from Definitive is not correct. First off the internal adjustment does not have to be done by Krell, any dealer can perform it as well as yourself with out voiding the warranty. Its a simple flick of a switch on the output stage after removal of the cover. No big deal. Also with quality tube designs as Audio Research there is no need to perform this task. The modification is done to prevent damage due to DC leakage from inferior tube designs. I ran my Ref II mk I into my Krell FPB-300 without any problems.