---
title: "Do Ubee Modem Routers cause 800 Number call termination?"
slug: "do-ubee-modem-routers-cause-800-number-call-termination"
updated: 2026-05-17T16:42:33Z
published: 2026-05-21T21:25:00Z
canonical: "help.8x8.com/do-ubee-modem-routers-cause-800-number-call-termination"
---

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# Do Ubee Modem Routers cause 800 Number call termination?

## Symptom

Calls to 800 numbers and specific area codes fail to complete.

## Applies To

Ubee Modem-Routers

## Resolution

1. Log in to the Ubee combo unit.
2. Go to **Advanced > Options** and uncheck the box to the right of SIP.

![](https://cdn.us.document360.io/e3a59e39-abd3-4423-964c-0a4008dc5673/Images/Documentation/clipboard_eb1d8d257ad27a2554c562ef14b1b3202.png?sv=2026-02-06&spr=https&st=2026-11-03T21%3A52%3A56Z&se=2026-11-03T22%3A52%3A56Z&sr=c&sp=r&sig=CRfHesEP3GW7MeIGVcH9ByezvQVQOTwx8by2ln5Brp4%3D)

## Cause

When SIP ALG is enabled on Ubee devices, it modifies the SIP packet headers and causes the carriers to reject the packets. This leads to issues that mimic call termination, and calls do not complete as expected.