If the mode is cool and fan is not on Auto Fan then the speed of fan should be continues regardless of cooling.
It should dispatch the air in a consistent pattern, not slow, high.
The drops on outdoor pipe can be the reason of cool air passing through pipes, incase the ac Gas is lessthan required you may notice Ice on pipes.
You are advised to discuss with Gree about this matter alongwith a very experienced guy in this field yourself for second opinion.
Note. The Air Conditioner is in warranty so No one else except Gree people should be allowed to open the ac