CaféX Critical Issue Bulletin 009 - No media to Chrome 53 for inbound calls with high round trip times (RTT).


CafêX have detected an issue when using Chrome 53 as the WebRTC client and receiving calls on server instances which have high RTT times (e.g. hosted services such as AWS) may result in no media.

If you are running an FCSDK version earlier than 3.0.5 (e.g. 3.0.1, 2.8.*, 2.16.*) then inbound calls maybe affected with Chrome 53.

Chrome 53 was available from Thursday September 8th 2016


Chrome 53 may expose an issue (multiple server hellos dropping the version number below spec) when experiencing high round trip times, so if you are hosting a CafêX WebRTC solution in the cloud you may experience no media on inbound calls.


Upgrade to FCSDK 3.0.5 or later.

If you have any queries about this behaviour or need to request access to the latest versions of Cafex software please contact

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