amp upgrade

I have been using CA CXA80 with B&W 604  speakers for about 5 years. I use Sonos streamer hooked up to the amp using optical cable. Also have some CD's and blue rays. overall sound is good but I always feel some punch and dynamic element is missing when I listen to the same titles with other random systems. Also the combo is not that expressive at lower volumes, sound gets a bit lost when volume is low. the other issue is lack of clarity in speech when watching movies. have to crank up the volume to hear the conversations but still a bit mushy.... When I bought the system I also auditioned an Arcam FMJ amp which sounded cleaner than the CXA80, I still remember it. it was not an option back then due to lack of availability. 
Wondering if upgrading the amp would solve this issue. I am looking at the newer stuff, preferably a steaming amp as most of my music is sourced from Tidal. Has anyone  used the Naim unity atom or the NAD m10 V2 ? are these any good? In particular something that can reproduce clean sound at lower volumes. I will at some point upgrade the speakers too but I feel I should be able to squeeze more out of them with a better amp? 

thanks