Funny you mentioned the bollinger bands, was just looking at that on this chart. They're tighter then they were back in Feb when it popped from .15 and ran.
For those that don't know, tight bollinger bands implies a tight trading range and a lack of volatility, and those phases often tend to lead to sharp price moves when the stock finally breaks out of it's range. Tight bands don't imply a move up or down, the direction can be either or (so look for other clues to help determine that), but tight ranges do lead to breakouts/breakdowns.
My guess is BAA has found it's bottom and will pop from here, based on how it's traded but also how the sector itself is now coming to life. Right now though BAA is stuck in no man's land, so which way it moves is yet to be seen. To breakout it will need volume, as you said, I'm specifically looking for a million+ traded and a break of .19 before I even start to get excited. However once it gets some momentum going, I don't think this will have a problem seeing volume build up, just have to wake it up first.
GDXJ is roaring today, as is gold and silver. The dip in the broad markets did not get bought up, first time i over 6 years we've seen that. IMO I'd watch BAA real close, perfect scenario for a bottom and ensuing rally, imo.