Turntable sibilance


Okay turntable Yodas, what is the primary cause of sibilance in vinyl replay? Obviously some records are badly cut & it's in the grooves, but I seem to have an inordinate amount of it.

I have a Shelter 501 mk 11 cartridge on a Rega RB 250 arm on a Nottingham Analogue Studios Horizon table. Running vtf at 1.8, but changing it in either direction makes negligible difference. Excuse my ignorance, but how do you change the vta on these arms, & might that be the issue? Setup was done by reputable hi fi store, spirit level says table is flat. The green sliding horizontal tracking adjuster doesn't seem to much either.

Any suggestions would be received gratefully.
houseofhits
You didn't say whether the sibilance was present more on the inner grooves(an indication of too little anti-skate)of the record.
Hi, brand new to the site. I have a few LPs that have a sibilance problem. These songs on these LPs are used as "test" songs to see if a new cartridge can track properly. In my experience, the higher quality stylus is about 75% of the cure. If you happen to have the first pressing of "Electric Warrior" by T. Rex, play "Jeepster". The harsh "sss" in this song will drive you crazy. How about "Black Water" by the Doobie Brothers? Who doesn't love that song? Near the end of the song the music fades and there's only vocals. The 'SS" is another example of sibilance. I have a couple carts that track these songs flawlessly, other carts sound aweful. I have a hyperelliptical that does an excellent job, DynaVector 10x4 does an awesome job. Invest in a cart with a nice stylus and I think you will be pleased with the result.