A little backstory: I am currently employed under a manager, who doesn't prefer to delegate tasks or share information on projects, such as what exactly to do, until when it needs to be done,... I don't think he is doing this on purpose, as I have talked to him, and the problem was fixed for a bit, but after a while it returns to the old ways.
He seems to always be absent on meetings, and rather than telling me for something to be done, he says "Hey, could you please do X thing if possible?". I don't mind him asking like that, but for me it feels like he is not too assertive in his role, and fails to give all the specifics to the project (I know this is usually not the case, but he doesn't provide the basics for it, and then does them behind my back, only informing me after he has done them).
Anyway, I am currently searching for a new job, the real reason being the manager. How should I hande the interview when they ask me the reason for quitting? Should I say anything about my manager, who is also my reference? They will check my references for sure, since there aren't that many. I don't want to lie in the interview, but also want the reference, since my performance reviews have always been very positive, and a positive reference can go a long way.
So to summarize; how should I talk about my reason for quitting, when I want to be truthful and transparent in the interview, while also not shedding a bad light on my current manager/employer.