I hawe same errors (kernel: 7986@C12L1ra0,Peer_Vendor_Spec_Action() 817: Peer_Vendor_Spec_Action:frame len check error) on stable : 3.0.0.4.388_33427 firmware, so I don't think it's related to the issue with web page loading.
The blue gear icon means Adaptive QoS is enabled on your router. With this feature turned on, regular websites load fine, but I’m getting errors when downloading large video files (around 16 GB) from the cloud and also when uploading big video files to the NAS. Upload speed also drops to about...
I checked how long my router’s been running and saw that blue gear icon — then I remembered I had turned on Adaptive QoS. After I disabled it, those little hiccups with webpagd loading started showing up again. But with Adaptive QoS on, my upload speed drops from about 920 Mbps to just over 500...