The Artist (is self published) or publisher (if you go through a company) are suppossed to get agreements for the number to be cut PRIOR to recording - or for small amounts as they are produced.

The way the laws read - it doesn't matter if they sell - it is the manufacture that you pay for.

When we recorded a cassette for a fund-raiser - the studio had to fill out a form showing the company that actually made the cassettes from the master that all fees had been paid.

airplay falls under "performance rights" - which is a whole 'nother issue and is a case of sample rates etc. Most small artists see little to nothing based on airplay.