Bass leaves after amp warms up?


I don't understand-after my Musical Fidelity M6i amp warms up for about an hour I notice the deep bass & kick drum aren't the same.
They sound less musical with loss of weight/depth.The notes are there but the moving of air have left.Sound is has much less impact and boreing.
I had the same problem with Bryston amp so there is no defect with amps nor with the rest of my equipment/
PSB Synchrony one speakers,AQ cables,Bryston CD Player.
My question has anyone heard similar & is there a plausable reason?
fishing716
We designed the amp to double-down into 4 ohms because we wanted it to have TRUE power, capable of driving MOST ANY speaker. I wanted a beautiful looking and sounding integrated with POWER and available dig. and analog options to make a no-compromise integrated solution.
Thanks and in look forward to your reply.
Sincerely,
Dan W.
I saw that you had listed your system for sale. Did you get to the bottom of the problem or have you just given up?
Fishing716... understandably you're selling the amp, but why the Synch One's?
He might be giving up which is understandable after a year of HiFi Hell, but I think he wants to start over with a different system. He obviously had a bad match. This is a common problem when reading reviews and assembling a system based on magazine recommendations.