4. Use the IC card to knock on the desktop during the audio test, and it can be clearly heard when inserted. The distance between the POS machine and the human ear should be 30~40cm, and there should be no hoarseness, broken sound, etc.
4. Use the IC card to tap the desktop during audio testing, which can be clearly heard when plugged in. POS machine needs to be 30 to 40CM distance from the human ear, no hoarse, broken sound and other undesirable phenomena.
4. In audio test, use IC card to tap the desktop, so that you can hear clearly when inserting. The distance between POS and human ear should be 30 ~ 40cm, without hoarseness, broken voice and other adverse phenomena.<br>