At the height of the endowment scandal, the FSA handled 1.5million complaints and took enforcement action against 10 firms.
More than £2.3billion was paid in compensation.
But today Simon Burgess from www.britishinsurance.com, predicted around half of the 20m PPI policies held in the UK have been mis-sold.
And with the OFT, FSA and consumer groups all expressing concerns, he said it won't be long before consumers realise they should be seeking financial redress.
Mr Burgess said: "While the FSA isn't yet producing PPI factsheets, claims management firms are encouraging people to pursue a claim if they feel they have been mis-sold PPI.
"With adverts regularly appearing in the media and marketing campaigns moving up a gear, consumer awareness of the potential for redress is growing. Potentially 10m PPI policies have been mis-sold which dwarfs the endowment debacle.
"PPI providers have been complacent - they haven't implemented robust processes to ensure their products are sold correctly.
"The tables are beginning to turn and David is taking on Goliath."
"Firms will suffer. However, those who have behaved honourably have nothing to worry about."
- Evening Times