I purchaed a 615 not one week ago. Hooked it up and the problems began. The router would work fine for a few minutes then seem to stall or hang. It confused me further because I could open up another browser window while the first was 'stalled' and google anything I wanted with no problems. It turns out that my cable modem was running at 10Mbps and did NOT like the 'auto' setting on the router set for 10/100.
SOLUTION: log into the router: Advanced->Advanced Network: WAN Port Speed. Change it to either 10Mbps or 100Mbps depending on how fast your modem is conneting. Don't keep it on Auto:10/100 Mbps.
Now my 615 works like a charm, even with my DWA-130 USB stick.
