Hmmmm are you in a location where you have close neighbours? Its sometimes easy for the 2.4Ghz band to suffer interference.5Ghz is a shorter range but higher bandwith and usually interference free.
Do you have a smary phone or a PC that you can scan the wifi looking to other networks and hopefully see which Wilress channels are in use. Sometimes changing the channel used on your AP (Wireless Access Point) works. Some not all AP's are smart and work out which channel to use but if there is "congestion" it can spent some of its time tring to find a "quite" part of the wireless ban. The frequencies used are country specific.
Its possible that the wireless clients (PC's etc) may require Driver updates if the new equipment is ultra modern.
I would check for congestion first. I have seen wireless disconnects when the Microwave is heating something up ..... definately not safe.
