>>bojan+(OP)
I live in Germany. 'Ja' here means 'ich stimme zu' only when explicitly asked. That's why Germans stick 'Ja?' after every second sentence. Ja? In general, 'ja-a...' means 'I hear you', same as almost everywhere else. That has been my experience.
>>nuance+X12
And why do they say ‘right?’ every time? Because without it my ‘ja’ does not mean ‘yes, sir’, but rather ‘I hear you, go on’. So, same as everywhere else.