I keep my LS25's gain at Med. You could test to see if the same thing happens when you play a CD. That way you can see if it is the phono preamp or not. You can also borrow a demo phono preamp from your dealer and see if that makes a noticable difference. Though I have never tried them, Vandersteen speakers are suppose to be a really good match with ARC amps.
I also did not like Cardas with my system either. ARC uses both Shunyata cables and power cords at shows. I just replaced both the power cables on my LS25 and Ref CD7 with Shunyata. I already had a Shunyata Black Mamba for my Ref 110. My interconects and speaker cables are old ARC Litz II.
I also did not like Cardas with my system either. ARC uses both Shunyata cables and power cords at shows. I just replaced both the power cables on my LS25 and Ref CD7 with Shunyata. I already had a Shunyata Black Mamba for my Ref 110. My interconects and speaker cables are old ARC Litz II.