For OBS it was reported to OBS, but closed with the comment "AMD is awaring about the issue"... So we have to wait for next driver update - i dont know how good a older driver (20.11.1) works with RX6000 Series but this is currently so only solution til update and fix is coming (may today with RX6900 Release)
AMD Ryzen 7 7700 | Asus Prime X670-P | Sapphire RX5700 XT Nitro+ | G.Skill Trident Z5 Neo 32GB DDR5-6000 CL30