General :: Razr And Galaxy Tab 7.0 Plus - Obtaining IP Address

Both of my android devicea, a razr and a galaxy tab 7.0 plus,are havingtrouble connectingto our wifi. the tab is on honeycomb, the razr on ics. assigning a static ip addressworks for about five minutes, then although the phone says connected, no connection works. during those 5 mins, i can browse the internet but cannot connect via dlna to other devices. when using dhcp dynamic ip address, it just cycles through obtaining ip to disconnected . i ued to use dlna daily, but no luck now, and the static ip is the only solution i can fimd online. This phone has used dhcp before, and theres no reason that it shouldnt be able to now. Both devices run standard roms.