Inner groove "Rumble"

Hi Lewm.....
As you requested up above, you can easily see my analog front end by clicking my system link. So, with all due respect, instead of telling us how Marakanetz's premise is flawed, can you please offer me some constructive advice as to what you may think about the problem I'm having. I would really appreciate your expertise. Thanks a lot.

..just a thought but the main bearing that holds the platter needs lubrication or replacement. That's what I would check first

Have you checked that the arm-lift is not touching the bottom of the arm when it reaches the end?
Some arm-lifts are not truly horizontal and if adjusted so that it has minimal clearance under the arm......can actually touch the arm?

Dear Adam, I haven't a clue. Typical reasons for what you are hearing are that some cartridges can pick up EMI from some turntable motors. Thus, as the cartridge nears the center of the LP, it gets closer and closer to the motor until at some point, hum becomes audible. But this is "hum", not "rumble". Grado and Decca cartridges, IIRC, used to be culprits in this sort of issue (the EMI-induced hum, I mean). Rumble is hard to describe, except I think of it as low-pitched and irregular in frequency. Like Halcro and some others suggested, make sure that there is no mechanical contact being made between arm wand and chassis or platter or other parts of the tonearm, as it sweeps across its arc. Does the cartidge get all the way to the run-out grooves, or does it get hung up? If the latter, then it is some sort of mechanical problem.

To all who have replied with good ideas ---- Lewm, Stringreen, Halcro, Pops, Marakanetz, and Nick --- Thanks a lot for your advice. I'm going to spend some "quality time" with my table and try out what you guys are telling me. I appreciate all your help, and I will post what's happening as I proceed. This is a great example of why I enjoy being a part of the Audiogon community ! Happy Listening to all !