Thanks hywelg
Thinking about it again, this is the only logical explanation anyway, so in fact my question was really from the dumber (not to be confused with "dumbler") side of life...but I cannot guarantee that I wont repeat asking for something that is not clear to me (like the impedance to be choosen if using an extension cabinet etc.
The amp and kleinulator did just arrive and I was so far only able to test the functionality of the OTS. It works well and looks great. Shipment to Switzerland was as well swift (within 3 days).
Mike