Rak Resort Maxi - weak flush

[Joe123]

Hi I've just had installed a rimless Rak Resort Maxi close coupled back to the wall loo.

From day 1 the problems have been:

1. It takes a couple of the big flushes to get rid of loo roll
2. The water when flushed doesnt travel all the way to the front of the pan and so leaves that area unwashed.

Any ideas?

The water in the cistern is at its highest level. Would a new flush valve sort it?

Lovely video attached...