Huster / Muster ? smps maker

[N_Cook]

Handscrawled in white on laptop sort of smps inside a Fischer in ear amp.
Anyone recognise the name? Presumably bought in by Fischer
Selectable between 12V and 24V by external (but inside the amp casing)
selector slide switch , other marking is
ATPS 2324, about 2005

 

[N_Cook]

probably Ansmann atps 2324 before branding up, bought in bulk by Fischer