Busking Permit for Berlin U-BAHN

What a wild goose chase we had with finding where to get a busking permit for the UBAHN (subway) in Berlin! We asked a police officer and he gave us an address of a building, but the person at the building said no, the permit office was at another place. But that place didn’t work out either. So, we pirated for a while until we got busted by the police. I have to say, the police were nice about it and gave us (finally) the correct address for the permit office. However, they gave us the wrong time and days. We trekked out to the permit office (which is located in a most inconvenient location), but discovered that the office was only open on Wednesday.
So, here it is, the official information on where and when to get a permit for busking in Berlin (since the information is not located anywhere else on the web):
U7 to Rathaus Stegliz (the permit office is in the station)
Wednesday 7am-11am
And that is the only time available to get a permit! Permits cost 6.40 euro per day, per person and are good for the following week. Don’t forget to arrive early, or else all the good stations will already be taken! Sheesh.
*no permit needed for playing above ground, unamplified*