Have you tried defaulting the router to factory default and reconfiguring it.
Once you get it defaulted plug a PC into one of the LAN ports and verify if it can connect to sites on the internet, then move it to the next port, and repeat until you run out of ports. Then consider the voice configuration.
It is possible to have any router get partially confused to the point that a power reset will not "fix" it.
Possibly trying a replacement power transformer might help. According to the chart at »
www.dd-wrt.com/wiki/inde ··· s#Belkin just about any 12 volt DC 1.5A power supply that has the right plug should work.
If all else fails I would consider reloading the firmware from a fresh download from Belkin and again reset it to factory default and repeat the port tests with a PC.