Skerdi, as some of the other replies have indicated, this is almost certainly due entirely to the source material. A couple of years ago there was a thread here about how "painfully bright" the M60s were on certain "well-recorded" pop items. Although my own listening is almost entirely classical, curiosity led me to borrow a couple of the CDs from the library and try them on my M22s. My finding was that the recordings were at times "painfully bright", which the M22s were accurately revealing. One of my receivers has variable bass and treble turnover frequencies and a treble cut of about 4-5 dB using the 3KHz setting tamed the problem, although it still didn't make the CDs good. Apparently this may be a boost in the upper midrange around 3-4KHz rather than the treble itself, designed to be more impressive on mediocre equipment.
As far as your Silvercats(and other equipment),this has nothing whatever to do with it; there's some discussion about these things that appears to be operating at a level of comprehension along the lines of silver looking brighter than copper, therefore sounding brighter too. There's no factual basis for such nonsense, of course, and your equipment is transparent. The speakers don't cover up the problems in some recordings and unless the listening room is very dead it won't either. A cut in the upper-midrange such as I described, using an equalizer, would probably help.
