A method for encoding an audio signal, wherein the method comprises: obtaining a first signal comprising digital samples that represent the audio signal at a first sample rate; wherein the first signal is obtained from a delay of an input signal comprising digital samples that represent the audio signal at the first sample rate; obtaining a second signal comprising digital samples that represent the audio signal at a second sample rate that is higher than the first sample rate; wherein the second digital signal is obtained from a sample-rate conversion of the input signal; converting the first signal into a first interim signal comprising digital samples at the second sample rate; wherein a quality of the sample-rate conversion for obtaining the first interim signal is lower than a quality of the sample-rate conversion for obtaining the second digital signal; generating a first difference signal comprising samples at the second sample rate that represent a difference between corresponding samples of the second signal and the first interim signal; applying a first lossless encoder to the first signal to generate a first encoded signal comprising samples representing the first signal at the first sample rate, wherein the first lossless encoder adapts its operation in response to first coding parameters; applying a second lossless encoder to the first difference signal to generate a second encoded signal comprising samples representing the first difference signal at the second sample rate, wherein the second lossless encoder adapts its operation in response to second coding parameters; and generating an encoded output signal that conveys the first encoded signal, the second encoded signal, and representations of the first coding parameters and the second coding parameters. obtaining a first signal comprising digital samples that represent the audio signal at a first sample rate; wherein the first signal is obtained from a delay of an input signal comprising digital samples that represent the audio signal at the first sample rate; obtaining a second signal comprising digital samples that represent the audio signal at a second sample rate that is higher than the first sample rate; wherein the second digital signal is obtained from a sample-rate conversion of the input signal; converting the first signal into a first interim signal comprising digital samples at the second sample rate; wherein a quality of the sample-rate conversion for obtaining the first interim signal is lower than a quality of the sample-rate conversion for obtaining the second digital signal; generating a first difference signal comprising samples at the second sample rate that represent a difference between corresponding samples of the second signal and the first interim signal; applying a first lossless encoder to the first signal to generate a first encoded signal comprising samples representing the first signal at the first sample rate, wherein the first lossless encoder adapts its operation in response to first coding parameters; applying a second lossless encoder to the first difference signal to generate a second encoded signal comprising samples representing the first difference signal at the second sample rate, wherein the second lossless encoder adapts its operation in response to second coding parameters; and generating an encoded output signal that conveys the first encoded signal, the second encoded signal, and representations of the first coding parameters and the second coding parameters.