Bought AX50 two months ago, happened inconsistent speed quite few times. Tried troubleshoot myself by temporary replacing the router provided by ISP TPlink archer c1200 and the new router AX50. 

ISP: UNIFI (TM) 
Subscribed speed : 500mbps 
 

Test on Archer 1200 
Lan Speed : 550mbps 
Wifi 5ghz : 360mbps 


Test on AX50 
Lan speed : 288mbps 

Wifi 5ghz : 290mbps 

 (when there is no issue on the AX50) 

Lan speed : 520mbps 
Wifi 5ghz : 510mbps 

The issue happens once in a week, but now seems like the issue happening since yesterday until now so far, the performance quite bad compared to the old router, i tried updating the firmware and restore factory default also wont help. Hope anyone able to help me in this issue and hopefully TPLink able to provide support in this matter and provide a better firmware update to fix this issue. Please dont make me feel regret of buying this 500 ringgit router. Thanks