I recently bought an RT1900ac to replace my Apple airport express.
No matter what settings I do it does not go into 1900 or 1300ac mode whatsoever. It's stuck in 5Ghz at channel 116 in 20Hz mode. This is really annoying and it's even slower download speed than my airport express that only has 100mbps links.
How can I fix this ?
Settings in my router:

Wifi connection spread:
