Results of recent perception experiments revealed that the signalling of rising-falling F0 peak categories in German intonation involves an interplay of F0 and intensity. Moreover, combining identification judgements and reaction times suggests that the abruptness of the perceptual change between the categories is determined by the signal dynamics in the sense of the durations of the F0 peak movements and intensity transitions. This undermines the use of categorical perception as an instrument to detect phonological intonation categories.