G900F update slow wi-fi problem

[robertantohi]

So, i just did a software update today through kies. Version is still 5.0, so no M.
My problem is, that downloads from google play, chrome and in general are now awfully slow- barely even 1 MB/s on wi-fi, whereas before they were 10 MB/s+
This is strange, because i ran multiple speed tests on ookla mobile app and it showed a solid 80 mbps up & down speed ALTHOUGH sometimes it would start off very slow at 1mbps and then go up towards the end.
I tried wiping cache partition, no luck.
Tried setting router thingy to static, no luck either.
Tried using an old router, that won't do either.
Any ideas?

 

[Rukbat]

Connect to your router using a browser. Set it to use AES encryption, not TKIP or TKIP+AES. Reboot it (just pull the power, wait 15 seconds and plug it back in.) You'll have to forget that connection and connect again. If that fixes it, you'll have to reset the connections for all other computers connected to that router. (Some routers have a different idea of what "TKIP" means than others.)