Stobo Babymonitor 400 Bedienungsanleitung Seite 21

Volume level is too high.
May be caused by the presence of another Babymonitor within the
area.
Strong magnetic fields / Shielding by metal parts / motor are close to
the units.
Reinforced concrete walls and ceilings in the surrounding.
Low battery level (Symbol on LCD display).
Antennas of both units are not pulled up