Blinking light on Westell 6100 DSL modem

The USB light on the front of my Verizon Westell 6100 DSL modem recently began blinking 24 hours a day, roughly once a second. What might be causing that? It's never done it before in the 3-plus years that I've had the modem. The blinking began shortly after anti-virus protection caught and quarantined a virus, so I'm wondering if my computer is perhaps still infected. All scans however now come up clean. I've re-booted computer and modem several times, and unplugged USB cable and plugged it back in, but nothing stops the blinking. The other lights do not blink. Any ideas or suggestions? how I can fix the Blinking light on Westell 6100 DSL modem from verizon