There are reports of DEF issues with the SVL95's. It is my understanding that Kubota is going to take care of them once they have a permanent solution for these issues. In the mean time, take it in, have them repair whatever is wrong (within emission warranty)-and make sure to get a copy of the warranty repair order and keep it for your records.
I have seen sometimes (other equipment) when the injector will leak, def wicks up the harness, gets into the ECU and the fix is to replace the injector, entire wiring harness, and ECU--and on that one, it's just temporary because the "new" parts are identical to the old; since there isn't a fix for that one. It isn't isolated to Kubota only, by the way. There's other brands having def issues too.