I'm going to agree with the others who have already posted and initially guess it is poor quality audio on the CDs themselves. The Adagio's measure extremely well with low distortion so it is very hard to imagine it is the speakers introducing something undesirable. Switching to the Ayre also supports this theory, as its zero-feedback design would result in less distortion during music clipping.
If you really want to be able to listen to these CDs without hurting your ears, then grab a different DAC or tube buffer that will attenuate the high-frequencies and only use that during playback of those CDs.
If you really want to be able to listen to these CDs without hurting your ears, then grab a different DAC or tube buffer that will attenuate the high-frequencies and only use that during playback of those CDs.