I had 3 rides of under 10minutes that resulted in the unit overheating and loosing all power, with a flashing red light and error 6.1 on the Tacx Training App (overheating). So I bought an external fan to blow onto the units fans while cycling, to see if that would cool it down.
So on the first day and my first ride with the external fan on (and having not used the unit for 2 days) was for about an hour, 32 km’s and everything felt great!
My second day (yesterday) the unit felt sluggish to start, giving the feeling of being on gravel or cobble roads but I was on a tar surface?, this then subsided and it was normal, then about 30mins in I was having to cycle at high cadence >100 in almost my lowest gear but my power was only at 2.2W per kg (struggling to keep up with the ride group I was riding with). Then at 45mins it gave up with zero power again 
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