Markbass Nano 300: Fan only runs when hot?

[PhatBasstard]

Just got one of these used but mint and working well, except........

I was surprised the fan didn't turn on when powered up (unlike my various Little Marks).
Anyone else experience this with their Nano? Is this fan thermally activated only?

The Markbass site and manual were no help.
I won't be able to play it enough to heat it up until next rehearsal.

Thanks