My husband and I use CPAPP (breathing) machines at nightare there 2 electric plug ins in the private berth compartments on the night train from Budapest to Krakow? Have you taken this train, were you able to get any sleep?
I'm afraid I don't know the answer to the plug-in question. But we were on that train last summer in a 6-person couchette and we had more trouble than usual sleeping. The main problem is that this is only about a 5-6 hour trip by train. To make it last 9 hours and call it an overnight trip, they make frequent and lengthy stops. The stops are not perfectly quiet either. The combination of a little noise and the stop & go was disturbing. We have slept well on other night trains.
There two one we were on from Krakow to Budapest last year.