Yeah, on the one hand, why would this be happening all of a sudden with the same burner, firmware, burn speed and media (is this a brand new spindle?)?
But...it certainly sounds characteristic of common burn errors which are most likely a function of poor, incompatible or "marginalized" media and/or inappropriate burn speeds...at least these are the "usual suspects".
I agree, the logical steps are: change media and reduce the burn speed.
I guess we'll wait to hear back from the OP with some specifics.