To eliminate interference on the wireless, try changing the wireless channel. Other wireless networks, microwaves, cordless phones and such can interfere with the wireless signal, even though you have a good signal strength.
Original S1 (Recycle Heaven)
Series 2 (PLS, sold)
TiVo HD (XL, PLS, "652")
Juliet Basic (4XL, PLS)
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!