So I’ve had similar experiences with Omegas. When I upgraded the stands, a lot of things got better, but the highs got a bit shrill. Type of amp didn’t matter. Turned off super tweeter, didn’t help. What did help was putting furniture coasters between the stands and the speakers. These are rigid, but have a soft material that is meant to protect floors on one side. I put that side towards the speaker. Works nicely. I guess I could mess with some blue tac, but why mess with a good thing? For my room, I have great sound now, and yes, it did take me many tries with speaker positioning. I also have subs, but only turn them on when I feel like it.