@shawn 

It varies making it difficult to pinpoint right away.

What has been tried so far?

What is the firmware build your router is currently using?

What does your network consist of?

When the slow down happens what do you do that resolves it?

@Tony 

I am on the latest firmware.

I tried turning off the 2.4Ghz network, that seemed to help, but now all I have is the 5Ghz network... kinda sucks.

I have a server that is connected via a cable to the router that I can access as a network drive. Not sure why but sometimes it is VERY slow with wireless access of the server. It is usually pretty fast when I access it from my desktop with a wired connection. When I transfer files too and from the server on my desktop I get around 100MBs read/write to the server. Over the wireless its usually about 30-40MBs but will drop down to like 1MBs out of the blue... Usually rebooting something somewhere will alleviate the issue although I've never had to reboot the server itself, it doesn't ever have problems...

@shawn 

You could try changing the wireless settings such as the version to WPA2-PSK, and selecting AES. This would apply to both bands.

If you do not have any AX devices change the mode to exclude that. For example, for 5G you would have a/n/ac.

One other setting is to disable WMM (Advanced > System Tools > System Parameters, uncheck for both bands).

@Tony It looks like it is doing better now. So what I did is I set my 5g network to Ax only, and my 2.5g network to b/g/n. I also down rated the security protocol for the 2.5g network to wpa/wpa2 personal with AES encryption. Now it seems everything is playing nice together, thanks!