I can confirm similar behaviour. When transferring files via scp when Jolla screen is OFF, transfers generally become sluggish or even stalled. I have noticed that if I try pinging my stby Jolla, I usually do not get any response and when I wake up the screen by double tap I see pings coming back from Jolla immediately. PS. My router is in the same room, quite new and powerful TP-link wr941nd