The last two nights we heard the skytrain running every few minutes when we went to bed (yesterday 2 am and Friday to Saturday between 3 and 4 am). 

 

I can not find some information that they have an overnight service now. Anyone?

Where are you?

 

There's no overnight service but testing on the section past Samrong is ongoing and also the re-configured signaling system will be being thrashed now that DTAC have turned their cell towers back on.

I see, that's a logical explanation. We hear it  running between Udomsuk and Punnawithi...

There are good choices about being close the the Skype train.

But, being able to hear it??... For me an early light sleeper, not a good plan...

Good luck I hope you get some sleep maybe a fan and ear plugs.

Trains have always been moved around during non service hours, I would imagine this happens quite often along sections involving lines that are being extended, as well as during the current signal debacle.