A network device determines radio frequency (RF) conditions at a first endpoint and a second endpoint of a call or session. The network device determines optimum first codec parameters for the determined RF conditions at the first endpoint of the call or session, and determines optimum second codec parameters for the determined RF conditions at the second endpoint of the call or session. The network device sends the first codec parameters to the first endpoint for altering operation of a first codec at a first device at the first endpoint. The network device sends the second codec parameters to the second endpoint for altering operation of a second codec at a second device at the second endpoint.