An apparatus comprising: a receiver (752, 754) configured to receive at least a portion of a bitstream, the bitstream comprising a first frame and a second frame, the first frame including a first portion of a mid channel and a first value of a stereo parameter, the second frame including a second portion of the mid channel and a second value of the stereo parameter wherein the at least one portion of a bitstream further comprises a quantized value representing a shift between a reference channel associated with an encoder and a target channel associated with the encoder, wherein the quantized value is based on a value of the shift, the value of the shift associated with the encoder and having a greater precision than the quantized value and wherein the encoder is configured to generate the received at least a portion of the bitstream; and a decoder configured to: decode the first portion of the mid channel to generate a first portion of a decoded mid channel; generate a first portion of a left channel based at least on the first portion of the decoded mid channel and the first value of the stereo parameter; generate a first portion of a right channel based at least on the first portion of the decoded mid channel and the first value of the stereo parameter; and the apparatus is characterised in that: in response to the second frame being unavailable for decoding operations, generate a second portion of the left channel and a second portion of the right channel based at least on the first value of the stereo parameter and based on the quantized value wherein the second portion of the left channel and the second portion of the right channel corresponding to a decoded version of the second frame. a receiver (752, 754) configured to receive at least a portion of a bitstream, the bitstream comprising a first frame and a second frame, the first frame including a first portion of a mid channel and a first value of a stereo parameter, the second frame including a second portion of the mid channel and a second value of the stereo parameter wherein the at least one portion of a bitstream further comprises a quantized value representing a shift between a reference channel associated with an encoder and a target channel associated with the encoder, wherein the quantized value is based on a value of the shift, the value of the shift associated with the encoder and having a greater precision than the quantized value and wherein the encoder is configured to generate the received at least a portion of the bitstream; and a decoder configured to: decode the first portion of the mid channel to generate a first portion of a decoded mid channel; generate a first portion of a left channel based at least on the first portion of the decoded mid channel and the first value of the stereo parameter; generate a first portion of a right channel based at least on the first portion of the decoded mid channel and the first value of the stereo parameter; and the apparatus is characterised in that: in response to the second frame being unavailable for decoding operations, generate a second portion of the left channel and a second portion of the right channel based at least on the first value of the stereo parameter and based on the quantized value wherein the second portion of the left channel and the second portion of the right channel corresponding to a decoded version of the second frame. decode the first portion of the mid channel to generate a first portion of a decoded mid channel; generate a first portion of a left channel based at least on the first portion of the decoded mid channel and the first value of the stereo parameter; generate a first portion of a right channel based at least on the first portion of the decoded mid channel and the first value of the stereo parameter; and the apparatus is characterised in that: in response to the second frame being unavailable for decoding operations, generate a second portion of the left channel and a second portion of the right channel based at least on the first value of the stereo parameter and based on the quantized value wherein the second portion of the left channel and the second portion of the right channel corresponding to a decoded version of the second frame.