I have the latest version 27" Imac and a Time machine.

I have DSL and have an Ethernet cable going from the modem to the time machine. Using TM as the router to the mac.

My first issue is that even though I have the 5 ghz network selected as priority it keeps choosing the 2.4. Why is that?
Also when waking the computer from sleep it takes about 10 seconds to reestablish a connection. Anyway to reduce that lag?

My second issue and more of an issue is I wanted to hook up my xbox to the network. It is non wireless so I moved the modem to the basement where the xbox is and connected it directly with an Ethernet cable. Turned on the Wi-Fi in the modem.
I can connect the computer to the network, but waking up from sleep it can take up to a minute for the Wi-Fi to show up in the available networks. Also I can no longer connect to the Time Machine.

If anyone has any ideas I would be very grateful. Even if someone had a cheap way to put a router or something on the xbox so I don't have to spend a fortune on the overpriced Microsoft adapter that would be fine also...