General Panda Cross - Intermittent Vibration??

[Spinoli1]

Hi Fiat folk. I've had my (new to me) Panda Cross for 10 days now, clocked up about 500 miles. I've done a fair number of motorway miles and on 2 occasions (only) I have felt the quite chunky vibration through the chassis (50 to 65mph), which only lasts for about 30 seconds.
It feels like what I would expect an out of balance prop-shaft to feel like, or a failed centre-support-bearing - but its only happened twice in 500 miles and then for only 30 seconds each time. If it was either of those things I would expect it to happen all the time, surely????
Can anyone advise me please?

 

[Herts Hillhopper]

There are a couple of earlier thread about this subject... try the forum search as i think they did get to the cause in the end

 

[Spinoli1]

Thanks HH. I have done some searching and there are plenty of threads about worn/unbalanced prop-shafts and prop-shaft components, none though that are definitive. What I'm really trying to understand is whether the fact that it has only happened twice in 500 miles and then for only 30 seconds-ish each time still means -
a) It is typical sick prop-shaft symptoms
b) Could it be anything else?
c) Whether it is an urgent fix or can be done when time allows