Wireless Bridge Dropping Connection

Hello,

Here is my network setup:

Comcast cable modem connected to D-Link DIR-655 (Hardware B1, Firmware 2.00NA). The D-Link is setup for DCHCP through a WPA2-PSK wireless network. I have a second router, Asus WL-520GU (Firmware: Tomato 1.25), running as a wireless bridge with a static ip (192.168.1.50). I have a USB printer connected to the ASUS (HP LaserJet 1018)

After initial setup, I can successfully print through the bridge using the static address (192.168.1.50), however, if I don't print for a while (a few hours or more) the ASUS bridge loses its connection with the D-Link router. If I unplug the ASUS and plug back in, the connection is restored and printing works fine.

Is there any way that I can force the ASUS bridge and D-Link router to stay connected?

Cheers,
Jon