The LEDs are flickering in a light tent (Puluz 60cm)

If I buy a new power supply it's either going to take an age or cost a
bucket in shipping.
Output 12V 2A 'constant current', dimmable.

So,
Why might it be flickering? Are these things servicable?

Does it matter if I replace it with something different that isn't
constant current but constant voltage?
Because I can't seem to find a 24W constant current driver operating at
12V, is that going to matter?

Any input.....