From the Roku website:
Try booting your SoundBridge in "Safe Mode" as follows: Unplug your SoundBridge from power. Next, disconnect the Ethernet cable and remove the wireless card. Point the SoundBridge remote control at the SoundBridge and press and hold any key on the remote (TIP: The arrow buttons are large and easy to hold down). Continue holding down the button and pointing the remote at the SoundBridge while you reconnect the SoundBridge to power. After a few seconds, the SoundBridge should boot with "Safe Mode" displayed on the screen. Choose "Reset to factory defaults" and follow the on-screen instructions to reset the SoundBridge.