My wifi signal strength and distance keep decreasing i keep lagging on my ps4 and playing videos in 4k is buffering also have multiple devices up to 15 devices using the dual band and still lagging the ps4 on the 5ghz and the router and modem is located in my parents room far from everyone in a household interior walls are concrete walls. what should i do get an updated router or buy an extender for better results especially for ps4 and 4k streaming. if so send link of best recommended devices