[quote name='solo4652' timestamp='1395349217' post='2401523']
@Happy Jack,
This is going to get embarrassing, I can tell. I have a Behringer BD1-21. It's entirely possible I don't know how to use it. I plugged my bass jack lead into the IN socket and then ran an XLR lead from the BAL OUT socket into an available XLR socket on the desk. I have no idea whether it was a mic socket.
[/quote]
OK, that should have worked. The XLR inputs on most mixers are there for mics, and they have independent Gain controls - usually a fairly small black knob at the top of the channel strip. You may simply have plugged into a strip where that Gain control had been turned right down for some reason.
The input signal level from a mic is absolutely tiny, so a mic channel strip should be more than man enough to take a signal from a DI box and boost it sufficiently.
One possibly irritating suggestion though - you mentioned that it is an active DI box. So what state is the battery in?