RAM passes and fails test 13

[Mickerson]

So I've been having trouble with my desktop randomly freezing where I am unable to input anything other than hard shutting it down.

I have been testing my RAM with MemTest86 and both sticks pass all tests with no errors when put individually in the recommended main slot (DIMMA2). However when testing both at the same time they pass everything but test 13, during which at some random point the program freezes entirely and again I have to hard shut down. I then tested both sticks individually in the other slot I use when using both at the same time (DIMMB2), and both sticks failed test 13, again totally freezing and locking up MemTest.

Does this seem like a RAM or motherboard issue? Any help is appreciated, thanks ahead of time.

Mobo: MSI B360-A PRO
CPU: Intel Core i5-8400 CPU @ 2.80GHz
RAM: G.Skill Aegis 16GB (2 x 8GB) DDR4 2666

[David (PassMark)]

Test 13 (hammer test) is special. As errors discovered in this test won't always manifest themselves in real life applications (but they certainly can).
See,
https://www.memtest86.com/troubleshooting.htm
Errors in test 13 also tend to be a design flaw, rather than a manufacturing flaw with an individual chip.

While it probably isn't recommended in the motherboard manual there is a reasonable chance you can use the other two memory slots. So that might be worth trying.