@MobileRouter Out of interest, I tested my samsung a25 phone on mobile data - isp tpg/vodafone australia. It exhibits similar behaviour to my MR600v2 (also TPG -updated to latest EU FW). When Idle or...

@m7200-Spain-Dev If it won't take the latest firmware, Try an older one.

@vegeta_ssj8 https://www.amazon.com.au/sim-adaptor/s?k=sim+adaptor Or a mobile phone/repair shop near you.

@vegeta_ssj8 You mean the adaptor from nano to micro that MR600 v1/2 use Or the SIM slot itself ? In the case of the SIM adaptor tray, Its very easy to just get it replaced.

@MARko19 Test it at least busy times; Midnight to early morning. If speed is normal; then its congestion If still the same, Put the SIM card into a phone at same location and re-test.

@SagaxRabbit Maybe this will unbrick it https://community.tp-link.com/en/home/forum/topic/706276?replyId=1422898 I read yesterday, It will take openwrt fw , and from there you can re-flash stock fw.