Problems making and receiving calls

General Problems

Problems making and receiving VoIP calls are often caused by local network issues.
This could be due to your internet connection, traffic congestion, a router's operation, or VoIP phone settings. Often these problems can be quickly resolved or avoided. The settings of your VoIP phones, Router and firewall may be adjusted so that you can use sipgate without any problems.
This help article provides steps that should help easily resolve issues in most situations. This article assumes that you have assigned your phone or extension numbers in your team account settings to the intended Group or User correctly.

Common errors which can be caused by a router and/or firewall include:

  • Your device does not register itself at sipgate (status "offline") or loses the registration after some time again.
  • Phone calls connect, but audio is lost in one or both directions.
  • Even though you've hung up the call, the phone continues to ring.
  • You can receive inbound calls but can't make outbound calls, or vice-versa.
  • You dial a phone number, but don't hear a ringing tone.
  • The call is disconnected after 5 - 30 seconds.

General Solutions

"Have you tried turning it off and on again?"
Issues due to your local network and its configuration may appear intermittently and unpredictably, sometimes only showing up after hours or days of problem free operation. You may find that powering your phones off and on may temporarily solve issues.

Update your devices' firmware
Make sure your router(s) and VoIP devices are using the manufacturer's most recent firmware versions. Purchase models with ongoing support, from manufacturer's providing regular firmware and security updates. Always check for known issues, before changing internet service providers, routers or VoIP devices.

Disable SIP ALG, if it's implemented by your router
Poorly implemented router SIP ALGs are a common source of issues with SIP VoIP.

Disable Stateful Packet Inspection, SPI, options in your router settings / Local port selection
When more than one VoIP phone or device is registering from the same local network (from behind the same router), please use different Local SIP Port and Local RTP (Media) Port values in the settings of each VoIP Phone.

Each SIP phone should use a successive SIP port like: 44160, 44260, 44360, etc (and same for the starting RTP port - 44104, 44204, 44304, etc.)

STUN server in your VoIP phone
Try using a STUN Server in the settings of your VoIP phone or device.
Our STUN Server is: stun.sipgate.net , STUN Port: 3478
The STUN Protocol is intended to help devices communicate from behind a router's NAT. STUN will not work correctly with all NAT setups, and in some cases STUN may resolve some issues only to lead to others.

Avoid the registration of VoIP phones and devices from behind more than one NAT or router
Where phones are registering from behind more than one NAT or router, please disable UPnP if your routers support it. You'd also need to compensate for the effects of multiple NATs on SIP traffic.
One double-NAT solution would be to setup port-forwarding rules (see below and here). Or, if you're connecting your own router to a modem-router supplied by your ISP, a solution would be to place the ISP supplied router in 'modem mode'.

Port Forwarding
If you still experience problems after testing with the recommendations above, you could give port forwarding a try.
You should first of all configure your VoIP devices to use static IP addresses.
Next, please port-forward the Local SIP Port and Local RTP (Media) Port range used by each of your VoIP phones and devices. Your port-forwarding rules should use the UDP Protocol.
Please be sure to forward a range of RTP ports (and not only the phone's starting RTP port). Each VoIP call will use an RTP port and an RTCP port. Forwarding RTP ports ranges like 44104 - 44120, 44204 - 44220, 44304 - 44320 should suffice.
With port-forwarding in use, please leave STUN disabled in your VoIP phone settings, with UPnP and SIP ALG disabled in your router settings.

Note: We can only provide general guidance and recommendations about the setup and maintenance of your local network. Your IT administrator, with your ISP's and device manufacturer's support, are best placed to provide in-depth assistance with your local network configuration.

Port Forwarding Guides and Ressources

www.portforward.com provides port-forwarding guides for many popular routers.

Gigaset

Information on operating Gigaset VoIP telephones with NAT routers

Gigaset VoIP telephones behind various routers with Network Address Translation (NAT)

DrayTek Routers

General Router FAQ - Port Forwarding

Fritz!Box

Configuring Static Port Forwarding

Virgin Routers

How do I set up port forwarding and port triggering on my Virgin Media hub? 

Some customers will be unable to resolve issues using the advice in this Help Article. In these cases, using the SuperHub in modem-mode and connecting another router to it will be the only reliable solution.

Enabling Modem Mode (SuperHubs).

BT Routers

Port-Forwarding Business Hubs

Port-Forwarding HomeHubs

Linksys

Setting up Single Port Forwarding on Linksys Routers

NETGEAR

Configuring port forwarding on routers with the NETGEAR genie interface

TP-Link

How to open ports on a TP-LINK wireless router

Technicolor

PlusNET Port-Forwarding Guide (TG582n)

Zen Internet Port-Forwarding Guide (TG582)

TalkTalk

Setting Up Port-Forwarding

EE/Orange

Port Forwarding with your Bright Box router.

Asus

How do you set up Port Forwarding by using ASUSWRT?

Belkin

Setting up Port Forwarding with a Belkin router.

Problems receiving Incoming Calls

If immediate Call forwards to another number fail, please check that you have sufficient call credit and then contact support confirming:

  • Your sipgate account number and phone number
  • Time of last failed call forward
  • The call forwarding destination number

If you're unable to receive VoIP calls at your sipgate number:

  • Disable call forwarding
  • Set up an immediate divert to your sipgate voicemail
  • Are you able to call your sipgate phone number from another line and leave a voicemail message? 

If you can receive voicemails at your number please try the following: 

  • Disable SIP ALG and UPnP in your router settings
  • Change the delay before forwarding to voicemail to 20 seconds
  • Change your phone's Local SIP and RTP Ports
  • Test with and without STUN enabled in your phone's settings
  • Test with a different phone installed on a computer or smartphone like  Zoiper
  • Are you able to call outbound? Can you reach the test number 10005? 
  • Some phones display three digit SIP Response codes on screen or in their logs. This code should indicate why registration is failing: SIP Response Codes - www.voip-info.org
  • If you're unsure of what to do next please let our support know.
  • Please describe the problem, the results of the steps you've taken so far and some sample call information along with the the model of your phone and router.

Problems placing Outbound Calls  

If you're having problems placing outbound calls after registering your VoIP phone online: 

  • Check that you have sufficient call credit to make the call
  • Check that the destination isn't a blocked international or premium rate number
  • Are you able to call 10005 and 50000
  • Check if you can call the same number from another line e.g. your mobile
  • Are you able to receive calls?  
  • Ensure that your VoIP phone's call blocking or dial plan options are not blocking your calls
  • Set your VoIP phone to use non-default local ports and test with and without the STUN Server option enabled
  • Some phones display three digit SIP Response codes on screen or in their logs. This code should indicate why registration is failing: SIP Response Codes - www.voip-info.org

If problems continue
Does powering off your phone and router/internet connection temporarily solve the problem? 
Can you call the number from sipgate using a different VoIP phone e.g. a softphone installed on a computer or smartphone?  
If the answer is yes to either of these two questions please contact the sipgate support. 
If you're contacting support please describe the problem, the results of the steps you've taken so far and some sample call information along with the the model of your phone and of your router: 


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