Hi Markd51,
That is what I was saying to do, back off the tracking force from whatever setting you are using now and do it gradually. I may have gotten a little long winded in my last post trying to explain all of the minute things I have experimented with to get this cartridge to sound its best, and when it does, you will know. I think the Lp is a sensitive cartidge and dialing it in takes some trial and error. I love sharing information with others who need help or have not tried things I did to make something work right.
Bottom line, yes, back off to about 1.7gm and listen to an LP, the same one preferrably and at the same place on the LP, take something you will want to reference with a wide dynamic range if possible to hear some cymbals, horns and drums. Then get a reference point and make your adjustment. Make sure you know what your initial tracking force setting was and then start experimenting. You may want to make a bold adjustment to see if there is a change in the sound characteristic at first instead of making all of the minute changes. I am interested in finding out what the cause could be, because I felt I had the same experience with some LP's that varied in thickness and this became even more noticeable as I put more hours on the LP.
Good luck,
Audioquest4life