Weirdest problem – only RTX 3070 get rejected shares mining RVN on BetterHash

I'm scratching my head trying to solve this weird issue. I switched 1 rig to mine RVN directly using BetterHash. It's a combination of 3060, 2×3060 Ti, 2×3070, 3070 Ti, 3080.

Only the 2×3070 keeps getting near 100% rejected shares using BetterHash, it's using NBMiner on KawPow. The thing is they work fine for months on a stable OC setting mining on NiceHash on all the miners including NBMiner on KawPow. They only get rejected shares when I use BetterHash. I gave up troubleshooting and just kept them on mining on NiceHash. Can anyone give some insights?