There were (are) at least 3 artists performing under the name A5 1)
A5 was a german 80s band from Bremen. They released only two 7 inches. The first one of 1980 called "Erstausgabe" was in an early german punk style (most popular song on it is "Seesack" aka Reeperbahn). The second one called "Kalte Erotik" is nearer to the german NDW style.
All songs and a lot of well recorded live tracks were issued later on a CD called '1980-1981 Mein schönes kurzes Leben' in 1995. 2)