Common Problems

This page lists frequently encountered problems and how to report or solve them.

Not a phone line

Beware that SIP2SIP was not designed to be used as a replacement for a national phone line. Special emergency telephone numbers like 911 or 112, or free numbers like 0800, or premium numbers like 0900 may be un-reachable when using SIP2SIP. All calls are routed in such way that they look as originating from abroad.

PSTN Caller Id

You may request the assignment of a caller id for your outbound PSTN sessions by opening a ticket in the support system. The credentials to login to the support system are available in the support tab of the account settings page

Beware that the caller id number may not always be presented always correctly, it depends on the behavior of the downstream PSTN gateways.

PSTN Quality

If you experience poor quality to PSTN destinations, we can report the problem to our upstream gateway providers. There is no guarantee that a PSTN termination problem will or can be solved but it helps us improve the service quality if we know when and what fails.

Device Configuration

Since there are thousands of SIP devices on the market, we don't know how to configure each and every SIP device. Please do not open a ticket related to how a particular device is configured.

Registration Failures

You must check the log of your particular SIP device for the packets is sending out and is receiving back from the network to troubleshoot such problems.

Session Failures

You can retrieve or check the log of SIP session from SIP2SIP servers. To report a problem about failed sessions, you must identify it and provide it together with your support request.

Login using your SIP account credentials to the sip setting page SIP account settings page. Go to History Tab. Each call has a Trace link, click on it to obtain the detailed logs of each call.

One-way Audio

To help us understand what may be the cause, you must do the following checks using Blink SIP Client on MacOSX or Windows:

  • Check if your volume is set right. Dial 3333, you should hear some music playing
  • Check if your microphone works. Call 4444 echo test number
  • Check if you can call another SIP2SIP info account if audio works both ways

Incorrect Rating

If you consider that you have been charged incorrectly for a PSTN outbound call you can request a refund. Please provide the session id when you open a ticket in the support system.

You can locate the cost for each session and a link to the session details in the Credit tab of your SIP account settings page.


For the payments you make with your credit card the following rules apply:

  • We will refund your payments in the first 30 days without any question if you have not used the credit. If you have used partially your credit we will refund the remaining balance and charge a 5 USD administration fee
  • We can guarantee the deposits you make for a period of 90 days from the date of purchase