Question DIMM slot works with 8GB stick of RAM but not 16GB ?

[Devorient]

I had two CMK32GX4M2E3200C16 (2 x 16GB) RAM sticks installed in my PC with XMP profile active for roughly a year. Suddenly, my PC started crashing and restarting after loading games.

Luckily I had two CMK16GX4M2B3200C16 (2 x 8GB) RAM sticks laying around so I tested the system with them, everything worked fine.

After some more investigation with the help of Windows Memory Diagnostic, I found out that when running with a 16GB RAM stick (regardless of which of the two CMK32GX4M2E3200C16 sticks) installed in DIMM channel A, a hardware fault is detected.

Some of my test results:

Channel A	Channel B	Works?
16 GB	16 GB	No
16 GB	-	No
8 GB	16 GB	Yes
-	16 GB	Yes

So I settled on a working configuration with 24GB RAM for now.
I am somewhat puzzled on where to place the blame and I don't have more parts on hand to test with sadly.
What do you think is the most likely cause of the fault? Any pointer on what I could try next?

Summary from HWiNFO64 (working system)
Computer: GIGABYTE B550I AORUS PRO AX
CPU: AMD Ryzen 5 5600 (Vermeer, VMR-B0)
3500 MHz (35.00x100.0) @ 3593 MHz (36.00x99.8)
Motherboard: GIGABYTE B550I AORUS PRO AX
BIOS: FFa, 07/11/2024
Chipset: AMD B550 (Promontory PROM19 C/C1)
Memory: 24576 MBytes @ 1600 MHz, 16-20-20-38
- 8192 MB PC25600 DDR4 SDRAM - Corsair CMK16GX4M2B3200C16
- 16384 MB PC25600 DDR4 SDRAM - Corsair CMK32GX4M2E3200C16
Graphics: ASUS DUAL GTX 1070
NVIDIA GeForce GTX 1070, 8192 MB GDDR5 SDRAM
Drive: KINGSTON SNV2S1000G, 976.8 GB, NVMe
Drive: ADATA SX8200PNP, 1000.2 GB, NVMe
Sound: NVIDIA GP104 - High Definition Audio Controller
Sound: AMD Family 17h/19h - HD Audio Controller
Network: RealTek Semiconductor RTL8125 Gaming 2.5GbE Family Ethernet Controller
Network: MediaTek RZ608 Wi-Fi 6E 80MHz Wireless Network Adapter
OS: Microsoft Windows 11 Professional (x64) Build 22631.4169 (23H2)