Try running some memory tests for starters. Not sure if you have you done that. You can use MemTest86 which is available through the BIOS. Could be various causes. In fact, have you updated ME Firmware or the BIOS recently? Are your drivers all up to date? I've had no RAM issues, but mine is slower speed - look at my specs.
Here are my currently installed drivers on the 690 Hero:
OS Windows 11 Pro 22H2 (22621.1194)
BIOS 2204
Intel ME Firmware 16.1.25.2020
Intel Chipset Driver 10.1.19222.8341
Intel Gaussian and Neural Accelerator Driver 3.0.0.1457
Intel I225 LAN Driver 2.1.2.3
Intel Serial IO Software 30.100.2221.20
Intel Thunderbolt Driver 1.41.1340.0
Intel Wi-Fi Driver 22.190.0.4
Management Engine Interface Drivers 2240.3.4.0
Realtek Audio Driver 6.3.9600.2347
UCM (USB Connector Manager) Driver 1.2.1.88
Intel Wireless Bluetooth 22.190.0.2
Intel Rapid Storage Technology VMD Controller 19.5.1.1040
Z690 Hero, 12900K, BIOS 4001, MEI 2433.6.3.0, ME Firmware 16.1.35.2557, 7000X Case, RM1000x PSU, ASUS TUF OC 3090TI, 2 x 16GB Corsair RAM @ 5200MHz, Windows 11 Pro 23H2, Corsair H150i Elite AIO, 4x Corsair RGB fans, 3x M.2 NVME drives, 2x SATA SSDs, 2x SATA HDs.