I fear I disagree with Mrug on this one. Interconnects really shouldn't change a whit over time, barring physical injury and corrosion at the jack. And in any event, except for either really bad IC's or really sensitive systems, the sonic difference in changing IC's is probably going to be remarkable only for its sublety. I don't recall anyone suggesting the MI 330s were particularly bad, so....
I can't recommend a cartridge, but it would be the second thing I looked to, AFTER testing and re-biasing your tubes (or replacing them, if the tests show they're done; and the re-biasing assumes the CP allows/requires such). But if your tubes check out, and the pre- and amp are functioning properly, then you'll know whether the cartridge is really what is making you unhappy, and proceed accordingly. (Bonus points - if you do the tubes first, other sources will sound better too!)
chas
I can't recommend a cartridge, but it would be the second thing I looked to, AFTER testing and re-biasing your tubes (or replacing them, if the tests show they're done; and the re-biasing assumes the CP allows/requires such). But if your tubes check out, and the pre- and amp are functioning properly, then you'll know whether the cartridge is really what is making you unhappy, and proceed accordingly. (Bonus points - if you do the tubes first, other sources will sound better too!)
chas