Then I'm back to my original statement. Other than slips you can't monitor for errors on D4, it has to be taken oos and tested ESF. I do realize the problems with all the different suppliers, but you report it too whoever you ordered it from and they deal with all the others. Unless of course you ordered base line to save money. Believe me most new techs don't know you can't reliably monitor errors on D4, I dealt with it for years.
Bill


Retired phone dude