I am writing this question here since TP-Link's tech support simply ignored me.

I seem to have some issues with QOS on my router. Once I change any of the options regarding the QOS (for example switch application priority from standard to gaming, or choose any of the devices in device priority), the connection becomes really unstable and webpages don't load anymore. It doesn't matter if I am connected through ethernet cable or through wifi. Plus it's not like I lose connection altogether - the pings still go both ways just fine, but the response times fluctuate a lot (ranging from 1ms to 200ms) and webpages simply don't load at all.

Anyone know what can be causing this or if there are any solutions?