sudden problem with E-MU 1616

Dear Cubase,
since last Friday - after 3 years of no problem, I’ve got some noises, crackling, popping, bad noise on playback. Not on the exported recording. I tried a lot of tips from several forums, some dating back to2005. All mention latency as the cause. I raised the value of the Asio buffer but that just seems to make matters worse. Any chance this might be remedied by updating the Asio driver? Or reinstalling Cubase? Playback from other programs sounds normal.
regards from the Netherlands