This article provides checklists for hardware issue and post required proof accordingly if issue persists.
1. Cannot power on device/No power hint on device
Try other power cord as possible as you can, test current power cord on other unit which is running fine.
If issue persists, take video for all LEDs presentation and video of current power cord which is working fine on other devices.
2. Cannot bootup device
Try these steps to factory reset it and see if it works.
1) Turn off the device power.
2) Hold the reset button and do not release.
3) Turn on the device power and wait for 5-6 seconds
4) Now release the button to clear configuration.
5) Wait for a few minutes for the device to clear and restore the factory settings.
If issue persists, take video for all LEDs presentation, it's helpful if it's possible to access ssh from console portal and share 'dmesg' command result as well.
3. No dialtone for some ports in TAS gateway
Try same steps to factory reset it like second case.
If issue persists, let us know if possible to make calls and take video for all LEDs presentation, it's helpful to access ssh and share 'dmesg' command result as well.