Hi Divo: You have to check every single parameter in the
tonearm/cartridge operation : Azimuth, VTA/SRA, VTF and antiskating, sometimes the sum (+) of little deviation from all these adjustement comes with a problem like you have, be sure the stylus is clean and "see" if the cantilever is right at the center of the cartridge.BTW, how many hours has your Ruby?.
Some day with one of my cartridges I have your problem and after to check all those adjustement the problem still exist, that time the problem was: a loose conection between the wires in the headshel with the pins ( dirty pin ) in the cartridge and a " weak " conection between the DIN 5 pin conector of the tonearm cable and the tonearm pins.
You have to check all these.
Regards and enjoy the music.
Raul.
