Quote The Red Bladder:
2. The agency could easily claim that they do not earn anything on sales at under $50.
Composers do have better tools now though to help them understand how/if/where their library tracks have been used. If you have a Tunesat account you have audio proof of broadcast (of course that's not proof of earnings though...) And the PRS/MCPS database has clear flags and months indicating when an MCPS payment has been made to the publisher (I'm not sure what Ascap/Bmi have along these lines). And I have heard of some publishers (who were known to be dishonest in withholding money) improving and now providing proper statements, presumably due to pressure from empowered composers to some extent.