Drop outs

Internet drops once every 30 mins or so also speed is all over the place not in accordance with the offered speed, I do operate in modem mode with eeros providing WiFi throughout the house. We always have had occasional drop outs but is getting worse, I am sure it’s a virgin issue and nothing to do with the eeros I have swapped these round to rule out this. Any thoughts I have rebooted very often with no joy. Thanks Kevin