Sibilance

No sibilance on any of the old quad torrents, the gold MSFL or the surround SACD.
Too bad for you.

You had me at

Some recordings I hear it, sometimes I don’t.

I'd look at cleaning up my AC power (AC conditioning) and some vibration free audio stands.

@lowrider57,
"There are different remasters of that album and they sound different. Sometimes it's hard to tell which version is being streamed."

I remember listening to a couple of 'remasters' back in the late 1990s of this and Led Zep IV and being disappointed at how they sounded no better than earlier (first gen?) CDs.

In fact it appeared as if someone had simply removed some of the tape hiss and elevated the treble response somewhat which resulted in a slightly less natural sounding disc.

I've been a little more wary of any so called remasters ever since.

There's also no doubt that some folks are more susceptible to this sibilance issue than others - and I'm certainly one of them.

I've witnessed people enjoying the sounds coming from loudspeakers that seemed to have ssuch serious treble issues that I could not listen through.
Having said that, I've never heard anything said in that regard about Magnepans, any of them.

I remember listening to a couple of 'remasters' back in the late 1990s of this and Led Zep IV and being disappointed at how they sounded no better than earlier (first gen?) CDs.

I have so many different Zeppelin remasters. You're right about removing tape hiss and tipping up the highs, that's what they did to so many rock albums. This was in the 90's before the use of high compression and The Loudness Wars.
I have excellent hearing, but also have a sensitivity to high frequencies.