A device for classifying heart sounds presented in a phonocardiogram comprising: a memory unit and a processing unit configured to classify heart sounds presented in a phonocardiogram by performing the steps of: - receiving a phonocardiogram comprising at least one cardiac cycle; - determining a first point in relation to a first heart sound in said cardiac cycle, presented in the phonocardiogram; - determining a second point in relation to a second heart sound in said cardiac cycle, presented in the phonocardiogram; - performing a first analysis on said heart sounds over a first time window, said analysis comprising the step of extracting spectral energies from said phonocardiogram, said first time window having a starting point essentially the same as said first point or an endpoint essentially the same as said second point and having a duration of a first predetermined time, wherein said first predetermined time is shorter than a time period (P1P2) between said first point and said second point; - when at least one further time window (wn) has a duration of a further predetermined time (Tn) wherein said further predetermined time (Tn) is shorter than said time period (P1P2), performing at least one further analysis on said heart sound over at least one further time window (wn), said analysis comprising the step of extracting spectral energies from said phonocardiogram, said at least one further time window (wn) having essentially the same starting point as said first point or essentially the same ending point as said second point, wherein said predetermined time (Tn) is the sum of the duration of a previous time window (w1, wn) and a predetermined time period (Δt); and - classifying said heart sound, presented in the phonocardiogram, as a non-pathological or a pathological heart condition on the basis of said first and the at least one further analysis of the heart sound over said first and at least one further time windows (w1,wn); characterized in that the first predetermined time and the predetermined time period are determined based on data from a database comprising phonocardiograms from several hearts wherein the phonocardiograms have been confirmed to belong to one out of three groups: no murmur, innocent murmur and pathological murmur. - receiving a phonocardiogram comprising at least one cardiac cycle; - determining a first point in relation to a first heart sound in said cardiac cycle, presented in the phonocardiogram; - determining a second point in relation to a second heart sound in said cardiac cycle, presented in the phonocardiogram; - performing a first analysis on said heart sounds over a first time window, said analysis comprising the step of extracting spectral energies from said phonocardiogram, said first time window having a starting point essentially the same as said first point or an endpoint essentially the same as said second point and having a duration of a first predetermined time, wherein said first predetermined time is shorter than a time period (P1P2) between said first point and said second point; - when at least one further time window (wn) has a duration of a further predetermined time (Tn) wherein said further predetermined time (Tn) is shorter than said time period (P1P2), performing at least one further analysis on said heart sound over at least one further time window (wn), said analysis comprising the step of extracting spectral energies from said phonocardiogram, said at least one further time window (wn) having essentially the same starting point as said first point or essentially the same ending point as said second point, wherein said predetermined time (Tn) is the sum of the duration of a previous time window (w1, wn) and a predetermined time period (Δt); and - classifying said heart sound, presented in the phonocardiogram, as a non-pathological or a pathological heart condition on the basis of said first and the at least one further analysis of the heart sound over said first and at least one further time windows (w1,wn);