A little while ago a reader wrote to say that he had found overdrive on some of his compact discs. This sort of news comes of course like a thunderbolt since it is assumed by most people that compact discs are examples of the quality of today’s digital technology. The first reaction to such an allegation is one of outright disbelief or at least scepticism. Moreover, it has been alleged by other readers that several producers have admitted (sic!) to overdriving, that is clipping, of CDs at the request of the relevant artists. Be that as it may, it was reason enough to design an indicator to bring overdrive to light and help the consumer in his/her quest not to buy flawed CDs.