A computer implemented method allows a user to adjust tracks in a musical arrangement. The method involves a user selecting a musical position of an audio track, which the user desires to adjust in time, either by compressing it or expanding it, by indicating with a pointing device, such as a mouse, the position in the time line of the audio track that the user wishes to alter. A first marker is then displayed at the selected musical position in the audio track. Boundary markers defining transients in the audio signal surrounding the selected musical position are then automatically generated by analysis of the audio signal, and are displayed on the audio track. The two boundary markers define an audio segment that is to be adjusted in tempo by the user moving the first marker along the time line.