ASD in an 11-year-old. On auscultation a quiet systolic ejection murmur was heard in the pulmonary area. It resembled the physiological sound but was longer. The second heart sound was clearly and constantly split. The finding is well depicted on the phono- and spectrograms. Echocardiography showed a 13 x 8 mm secundum type ASD. Pulmonary artery flow velocity was 1.7 m/s and aortic flow 0.9 m/s. Because the ASD secundum murmur is caused by increased pulmonary artery flow, the sound is sometimes difficult to distinguish from the physiological sound. In such cases, attention should be given to the possible splitting of the second heart sound. Area of auscultation: left second ic space (LIC2). Duration 91 %, peak frequency 126 Hz, volume 19 %.