Disclosed is a method in a network element of a communication network, which communication network is capable of transparently transferring coded data at least in some part of the communication network. The method includes detecting a need to change codec rate to a second codec rate in a downlink connection from the communication network to an end user device; receiving coded data destined to said end user device, which data is coded with a first codec rate, and starting, in response to said detecting, rate transformation for transforming codec rate of said data destined to the end user device into said second codec rate. Also disclosed are an apparatus, a system and a computer program.