By following this guide, you should be able to rescue a bricked V300, eliminate echo and call drops, and extend the life of your VoIP hardware. Remember: always match the firmware version, never interrupt the flashing process, and test thoroughly after each step.
The correct firmware depends on your hardware version. Always check the label on the bottom of your router before proceeding. : Use version V300 (Standard) : Use version Tenda Global How to Apply the Fix How to Check the Firmware Version on a Tenda N301
After any firmware fix, perform a factory reset: