Give us some information about the current format. What day(s) and time(s)? How regularly? How much variety of artist, format, type of entertainment? Did you ever have large crowds? How long ago?

Maybe just writing this down will help find the problem. Maybe the crowd is bored with something and you need to provide some more variety or not hold as many events or ...

Is this a performance venue? Is it participatory? Song/perfomance circle? Concert series? Do you charge admission? Is there a conflict with another popular event?