Friends Internet lags when my parents use foxtel?

Hi first time user looking for help.

So I'm posting this on behalf of my friend, my friend uses a pretty cheap looking usb wifi adapter that was left behind by big pond worker who was fixing his internet a few years back, he says when his parents use internet on their phone or use the TV to watch foxtel or watch youtube on the TV that he's net will loose it's strength and keep disconnecting, he can't maintain connection for more then 2-3 minutes when this happens.

Would a way to fix it be by getting him a better wifi adapter like this? http://www.jbhifi.com.au/computers/n...pter-sku-66130 , I just want to help him fix his net.

Thanks for the help, and please reply as soon as possible.


Thanks.:)