That's where I was at with my FX DRS Classic. That air tube gives off an odd sound. The only one I have that cured it was the Weihrauch XL. I have heard the Huma air 40's are effective as well, but I don't have one. I put the Ronin on and it still had an odd sound.
The best in the business couldn't do that 20 years ago at the pinnacle of break barrel airguns. If they still made the Theoben Eliminator they would probably sell for around 2K.
I have the original FX, but I was looking for one that can do airguns and firearms. I like Athlon as I own several of their scopes and I liked it better in reviews versus Labrador and the Garmin.