Phone Not Connecting via Ethernet


polycom soundpoint IP phone says DHCP failed when connected to wlan on USB 3.0 docking station but it works when connected directly to the wireless router.


Hi There,

Thank you so much for reaching out to us, I am sorry that you are running into this issue, but I would be happy to assist!

If you are directly connecting the individual Polycome SoundPoint IP VOIP phone to the docking station, then this is typical behavior as the individual docking station relays the Ethernet signal via the DisplayPort chipset contained inside of the docking station, which requires specific drivers in order to function. These individual drivers are not available on VOIP phone systems, as they utilize companion or embeded software operating systems to function, and DisplayLink drivers are not compatible nor built in for these specific devices.

Are you directly connecting the phone, or utilizing a companion software or device via the system, and then connecting the laptop via the Ethernet port?

Thank you for your patience,
Product Owner & Technical Support


Hi Everyone,

We attempted to reach out to Christopher to advise him on the compatibility of utilizing a VOIP Phone Device directly through our Ethernet port on the UD-3900, but we did not receive a response back.

In order to utilize the DisplayLink based Ethernet and devices on the UD-3900, the individual host system or device needs to support the usage of DisplayLink based drivers, which are currently not available on VOIP phone devices.

If anyone has any similar questions or concerns, please feel free to reach out to us directly at, and we would be more than happy to answer any questions or troubleshoot in any capacity.

Thank you for your patience,
Product Owner & Technical Support