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Linksys Support

Cordless Internet Telephony Kit (iPhone®) (CIT400)

• Hands-free Speakerphone with one key touch
• 120 hours standby time and 10 hours talk time
• Expandable up to four handsets with a single base station
• 2-in-1 Cordless DECT telephone for Skype and standard telephone lines

Support Sections

FAQs are frequently asked product questions. Select Downloads for user guides and firmware updates.

  • Overview
  • FAQs
  • Frequently asked questions

    Frequently Asked Questions for various Operating Systems

  • Forums
  • Forums

    • QoS - Upstream Bandwidth

      1. It helps a lot if you post the router you use. Different models have different settings.2. Generally, it's correct what...

    • CIT400 handset registration failure

      The "Page" button on the base must be held pressed for 20 seconds to register a handset. This info is from Linksys...

    • CIT400 connections

      The CIT400 needs one (or two) connection(s) to work:An ethernet connection which ultimately gets its own IP address...

    • CIT400 configuration

      There is a difference between Skype on the PC and the CIT400 when one uses a satellite link with low upld speed (approx...

    • WIP320 Silent Mode Bugs

      Well, if you, like me, happened to notice a new icon on your WIP320 screen (a crossed music keynote) you might start to...

    • CIT400 Freezes

      I fixed my phone. 1 day online until know. This is what i did. I use 220 V, so i had to use an adaptor since the phone comes...

    • CIT400 Linksys Phone Does Not Sign In With Time Capsule

      SIP uses 5060 - 5061,but it depends on what was set on your phone connection and router.some are listed here I...

    • Wired and Wireless - Adding a Second Router

      The settings on your wired router should remain the same. All you need to configure is the wireless router. To configure...

    • E4200 Static IP Issues

      Haha! Oh man! Late nights just aren't good. I realized my error in the morning. I had previous used the Advanced Routing...

    • Cannot renew ip address

      Un-install the adapter software/linksys monitor and install only the drivers... Remove the Linksys Adapter and un-install...

    • Having Trouble With My MTU Settings

      Follow this, It will surely work...Open an Internet Explorer browser page.In the address bar type - username...

    • VPN attack detected in VPN Log

      Yes, we have a VPN tunnel to another RV082 but it is disabled. Could this be the problem Thanks Oliver

  • Downloads
  • Downloads

    Please ensure you select the correct hardware version as not all downloads are compatible with your device.

    Where's my model number?

    License Agreement

    How to find your model or serial number

  • Videos
  • Live Chat
  • Live Chat

    Live Chat Not Available
    Please use our forums
    and Knowledgebase,
    and check back later
    for Live Chat availability


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Live Chat

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