Another potential issue here.
I used my 945 for the first time in a lake swim, and after swimming for 1h 7 m and what should have been a 3100 metre swim only recorded as 32 m on the watch.
On checking on Garmin Connect this morning, it only recorded the first 32 metres of the swim and then seems to have lost GPS.
I have recorded stroke rate however through the swim and of course, pressed the lap button on each lap. So the watch was still actively recording the swim, just not the distance.
I am swimming again on Saturday or Sunday, so i will update further if this issue continues.
If it does, I will log it with Garmin.