This story will tell you not to simply give up on your BH.
If you experience a very disappointing result with your BH you need to follow this guy from Vietnam.
I knew him only via the net and he seems to read my blog very often.
His real story was some thing like this:
He used to own a very disappointing low performing BH.
He tried to get help from a number of " birdhouse consultants" but all failed to live to his expectation.
After seeking help from the internet he got hooked to my blog website (http://swiftletfarming.blogspot.com).
He reads all my strange ideas and tried a few as per my recommendations.
He took some trouble to call me one day and asked for some new sounds and those liquid super pheromone.
He ordered 5 liters of the super pheromone liquid plus a set of good sounds (Super 208 and superbabyking).
After installing more tweeters, cleaned those nesting planks, applied liquid super pheromone, changed the internal and external sound to Superbabyking and Super 208 respectively his BH jumped from 50 nests to 100 nests and soon after to 300 nests.
The 600% increment happened within 4 months.
A wonderful story and please read his exact word to me recently.
He called me Master :