Abstract: A method and apparatus for decoding a bitstream (100) of transform coded multi-channel audio data. The bitstream is subjected to a block decoding process (101) to obtain for each input audio channel within the multi-channel audio data a corresponding block of frequency coefficients (102). Each block of frequency coefficients (102) is assigned a higher precision inverse transform or a lower precision inverse transform according to predetermined characteristics of the audio data represented by the block. The blocks of frequency coefficients are subsequently subjected to the assigned transform (105, 106) and an output audio signal (108) is generated in response to each of the higher and lower precision inverse transform processes.