Are you using RAM that is specifically compatible with Ryzen? I am no expert on the topic, but I believe that it is much better to get that type of RAM due to all DDR4 RAM being optimized towards Intel atm (heard this from JayzTwoCents).
The RAM works fine. Literally the only issue I have is with the speed not going over 2133Mhz with 4 slots filled. If I remove 2 modules, the speed jumps up to a max of 2666Mhz on 3000Mhz RAM. Because I have noticed no change that you can actually feel, for aesthetics I just leave all 4 occupied until/if/when optimization happens.
I heard this from Linus Tech Tips. Apparently the AMD RAM doesn't preform much better according to benchmarks.
But no, I am explicitly saying that AMD has trouble addressing high frequency RAM. AMD is supposedly working on the problem.
I haven't looked into it recently but I do know that it was being mentioned.