Fix a desk phone: No Service, Register Failed, no audio

Find what your phone shows, then follow that fix.

No Service

A Yealink phone shows No Service when no line on it is registered. Yealink gives two causes: the phone isn't on the network, or its line failed to register.

1. Press OK on the phone. If the status screen shows no IP address, the phone isn't on your network. Check the network cable at both ends, or the Wi-Fi on a T54W.
2. If it shows an IP address, the line didn't register. Go to Register Failed.

Register Failed

The phone is on your network, but Tonet's phone server didn't accept its line. Check these in order.

1. The details match SIP Information exactly. Copy them again from Manage › Users › the person › SIP Information (how):

• The user name, and the authentication ID if the phone has one, are the User Name: a u and a number, like u12345. Not the extension, not an email address.
• The password is the Password. Use the copy button, or click the eye to check what you typed.
• The server includes the port. Grandstream phones take the whole Domain. On a Yealink, the part before the colon goes in Server Host and the number after it in Port.

2. Domain shows None:None. Your account's phone server isn't set up. Email support@tonet.ai.

3. SIP ALG is on in your router. It can change the phone's traffic so the line can't register. Turn off SIP ALG.

4. A firewall blocks the phone. Yealink lists firewalls and access lists between the phone and the server as a cause. Let the phone reach the server and port in Domain.

5. Settings left from another provider. A phone from another provider can keep that provider's settings, or run its firmware. Factory reset the phone, then enter only Tonet's details. Your phone's guide has the steps.

6. Old firmware. Yealink's checklist for failed registration includes updating the firmware. Your phone's guide shows how.

Then restart the phone and check its status again:

One-way audio or no audio

The call connects, but one side hears nothing, or nobody does. Yealink and Grandstream both point to the network first.

1. Turn on STUN in the phone. Server stun.tonet.ai, port 3478, and set the line's NAT setting to STUN. Your phone's guide has the steps.
2. Turn off SIP ALG on your router. See Turn off SIP ALG.
3. Check firewalls. Yealink says that when the server sends the audio and the phone still gets none, the cause is usually the network, like a firewall. Grandstream says to make sure firewall rules let the audio (RTP) through.
4. Rule out the handset. Try the call on speaker or a headset. If those work, the handset or its cord is faulty. Check the handset is plugged in and that the other person isn't on mute.
5. Several Grandstream GRP or GXP phones on one router? Keep Use Random Port set to Yes, the default. Grandstream says it's usually needed when several phones sit behind the same router. It's on the same page as STUN Server.

Still stuck?

• In the dashboard, click Report an issue at the bottom of the left menu. Under Where did it happen?, pick Desk phone, describe it in What happened?, and click Send report. We reply by email.
• Or click Ask Tonet at the bottom right of the dashboard, or email support@tonet.ai.

Say which phone model you have and what its screen or status page shows.

Next step

• Turn off SIP ALG on your router
• Find your SIP details again
• Setup guides for each phone
• Replacing a phone? Tonet sells phones that arrive set up: tonet.ai/desk-phones