Muted hi freq from Magnepan 1.7

I own a pair of 1.7’s that seem to sound muted in the hi frequencies. The cymbals are there but not as pronounced as I would expect. It’s happening on all my playback from mostly red book CDs. 
 

my system is modest 

ARC SP 9 mk2, Odyssey Khartago,

Cambridge Audio CXC, Denafrips Pontus 2. 
 

Hope my hearing hasn’t deteriorated that badly but during live concerts I can clearly hear hi frequencies. 
 

Thanks