I faced this situation.
If you have a really serious situation where the EM keeps shitting on you, take him to a cabin and have a word. Understand the core issues. Get some leverage over them.
Best way for him/her to flap their gums is to get them drunk at a party and then understand why the fuck are they doing this. Get leverage and get them workin.
They either disagree with your decisionmaking capacity (manageable) or want to become a PM themself (manageable). If they are setting you up for failure everytime, reason with them or simply escalate.
EARN. THEIR. RESPECT. Simple as that.