i would not be surprised if that's the issue here. we have a literal dinosaur of a Cisco that desperately needs replacing. this might be the ammo i need to push that over the edge (literally, if they'll let me). thanks for the heads-up on that. that just saved me hours of generalized combing through my running Wireshark capture. you da boss, Phil. 
off i go to dig through hardware specs and do come specific testing to confirm if that's the case here.
EDIT: blow me down, that's the answer right there. our Cisco shuts down web sockets after 30mins of inactivity. 
unless you turn the firewall off. gotta love it. 
time for a new Mikrotik (yaassss....).