Unbearably incompetent new associate.

I work in a boutique firm. We have a collegue who joined at an associate level 10 months ago, who:

1. Never worked in our industry focus and hence doesn't know specifics
2. Passes all asks and requests to analysts
3. Generally doesn't understand what's going on and doesn't produce any actual work - instead he tries to be silent and unnoticed day-to-day
4. Arrives at 10am and leaves a minute after the MD does, usually 4pm (then pretends he is online on teams until 9pm and schedule sends a random email to a client at midnight)
5. Was hired as an associate although his skills are intern at best just because of his age and the fact he graduated MBA
6. He is just unpleasant being around with, burps and eats loudly at the desk
7. Takes all the calls from phone booths so the others do not hear him
8. Everyone at the company knows he is an idiot except the MDs somehow. I struggle to understand how is it possible to go 10 months unnoticed
9. He has been staffed on a single deal for 10 months now and stays silent when new mandate comes up so he doesn't get overworked. Average for team members is like 4-5 in the same time by then

I am just so annoyed just by his presence and the fact the guy makes 2x more than me although works 15% of me and others at best.

Anyone with the same experiences? What should I do?

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