Had trouble installing the new CP-1 with my v2.400. I had to file down the dovetail-type mechanism that holds the pre-amp to the speaker just to get it to slide in. How annoying!!!! I also was unable to remove the stand on the speaker as instructed, despite using a powerful electric drill/screwdriver, almost totally stripping the screw. I had to slightly bend the stand to get the CP-1 to slide in (after filing the pre-amp) because I was unable to remove the stand. URRGH!!! Let me know if anyone else has had this problem. On a lighter note the CP-1 completely removes the crackle when changing the volume (thank God), and everything sounds a little crisper.....mostly the bass.