Co-op campaign input lag?

When Halo: CEA launched for PC, my friend and I did some co-op missions, and it ran like butter. Everything was smooth af, and there was no lag or anything, and it was a great time. Last night, we tried to continue our playlist, and whoever was not the party leader was always experiencing heavy input lag. Like almost 0.5-1s delay. This applied to any action–moving, running, jumping, shooting, you name it. Is this just server stress because everyone is trying to play due to coronavirus quarantines or something? I figured co-op was p2p, but both of our internet connections were golden–running the exact same numbers we always get. We were also not running any other taxing programs, and our PCs are more than cut out to handle this.

So yeah, I’m just wondering if anyone else has experienced this, and if this is related to an increased volume of players, or if this is a new bug, and if so, when it will be resolved. Thanks.

ADDENDUM: I have also verified the integrity of my game files just to be sure it’s not that.

Happened to me today. When searching this was the first page I found.

its been there for a long time… i play with my friend abroad… the input lag was there on mcc while i tried to play on xbox with my friend… and again we tried on pc … the input lag still remains … sad…

Bump, We we’re playing halo 3 on Xbox one MCC. The game as awfully laggy, each movement would take a second to register. And sometimes when there were lots of things happening on screen the game would freeZe up.

Sierra 117 took probably three times longer than usual to complete because of this.

It always has been like this. I remember trying to play with my friends on the backwards compatible version of reach and it still was laggy for everyone except host. Then we tried reach on mcc and it still was…laggy. Now me and a friend have mcc on very good pcs. I have 20-30 ping and my friend has 20 ping and you know what. It. Still. Lagged.
It just so sad because yesterday everything went fine but just sometimes my friend had lags but very small ones because dont have wired connection. But now he told me that it was unplayable then we switched host and it then lagged for me. I reinstalled mcc, rebooted my. I did everything. But it still lagged. For some reason Halo CE doesnt lag.

So to sum up, if you didnt get it. It will never be fixed.

The only way you can help out here is to make sure that the only thing that is using your home internet is your console.
Make sure there are no downloads happening on you or your co-op partner.
Use a wired connection if you can.

Follow this for both the host and the peer. Not much else you can do.
If nothing else is using your connection, open the MP connection test on your Xbox, its in the settings. Test the connection speed. Whoever has the fastest speed should be the host.