I'm sorry, I can't answer that. by the time you have a machine, it is really not analyzable, you would have to do that at the host level.
But if there are noticeable problems with them, then my guess it is the host machine producing such "artifacts" the old fashioned dahdi_test -vv might show something but generally modern asteri use kernel based timing , and the kernel you are using is running on "who knows what I am doing" 