Was once stuck on the ground at LGW / EGKK for 4 hours.
Skipper got on the PA and described the basics of the problem (problem with undercarriage) and stated it was being worked on. Said that updates would be provided every 30 mins or when there was new news.
Sure enough, roughly every 30 mins, either the skipper or F/O got on and said along the lines of "nothing new to report, problem still being worked on and we'll let you know when we have progress". One time was problem identified, new part being requisitioned.
Then after 3 hours it was new part being fitted, it'll take about an hour.
Everyone was reasonably happy because at least there was some info flow.