Could you try running the memory @ stock, just to debug if it still happens?
Are you running custom timings for the memory or XMP? If only XMP it might be that secondary timings don't actually play well with your CPU/Memory combo. My nephew's 3800X had a similar issue (his XMP profile @ 3600 Mhz wouldn't even boot) and setting custom timings solved the issue and offered a nice perfomance boost on top.
This guide is a decent starting point:
The tool for calculating correct timings is this (also works for threadripper, but make sure you select the correct options):
DRAM Calculator for Ryzen helps with overclocking your memory on the AMD Ryzen platform. It suggests stable memory timing sets optimized for your m
www.techpowerup.com
You'll need a memory test to validate that your memory is stable (you can run that at 3533 as well to validate it's actually stable). If you're running windows (which mighy not be the case considering the CPU) I recommend
Karhu MEM-test for that. It costs, but it finds the errors super quick (usually passing 100% means you're good), while other memtests need hours to run. If you're on Linux then
this tool should also work.
Also obviously always try the latest BIOS and latest OS version (kernel).