Slow write or download speeds under 1mb

Big Sur 11.5.2 Opencore SSD WD Black SN750 NVME Skylake i7 6600u HP folio g3

I can download fine for a couple minutes then I’m crawling at kb speed. Internet speed and drive speed test fine but actual performance is as described. I think it’s a trim or other SSD issue. I have NVMEFix and CtlnaAHCIPort kexts and force enabled trim. I once had it working enough to download a couple GBs but it always drops back down to kb/s speed. I’ve been trying for a couple days but can’t seem to figure it out. I thought maybe it was the multiple partitions on the SSD but reformatting to 1 didn’t fix it. I’m on the latest firmware for the SSD as well. Any ideas?