I don't think many computer CD drives have ever exposed the error correction to the computer. It's usually handled entirely internally, as the link shows on the

I don't think many computer CD drives have ever exposed the error correction to the computer. It's usually handled entirely internally, as the link shows on the last page. What that program was probably doing was trying a bunch of times to read the same area from a bunch of different starting points to see if it could tease out the data with a little luck. >math caused the slower reads. The error correction was ALWAYS being done, and that math was done on a dedicated circuit.