Venu takes ages to restart after auto-pause

I have a Venu and typically only use the Walking activity.  I have it set to Pause "When Stopped".

Lately it has taken to pausing almost immediately on "When Stopped" which is fine since yes I have stopped to cross road etc etc but it then takes an age to restart.  I can walk for circa 200-300 steps before it kicks in again but today I walked 0.25mile and it never restarted.  GPS has clear open view of the sky so it's not like it has lost GPS signal.

It is doing this regularly so I'm losing anything up to qtr or half mile an activity and I do 3-4 GPS logged activities a day so I'm losing out massively on distance.

I can't say when I noticed this behaviour starting but it's been a few weeks and I'm sure have had an update in that time.  I am not in the beta programme and I don't want be factory resetting my Venu if can help it. 

Richard