Thanks for the additional information kswalls.
When trouble shooting strange issues like this, I like to consider all the related factors, and rule them out one by one to pinpoint the issue.
I would try a new cartridge, in case the cart you've been using for the past few years isn't providing good ink flow like it used to.
If this problem is similar to how the printer was acting before installing our inks and carts, then I would say the carts are unrelated, and would look into the printer more, such as the ink lines. I've also experienced a brand new damper from Epson was defective, so even though I had just replaced the dampers, a channel wasn't working well, and after trying everything else (thinking it couldn't possibly be the dampers, since I had just replaced them), I discovered one damper was bad, and the printer worked great again after replacing that one damper again.
When were the dampers replaced, and other parts cleaned by Epson? Have you ever cleaned your printer following our instructions?