I don't get it! It's a documented URC issue! Escalation report number ESC-911.
Those CI's that claim it doesn't exist haven't updated their CCP and downloaded it to the remotes in the field. It's also been documented in at least one thread here on remote central that this problem started happening consistently with one of the latest CCP updates.
Before you claim this "Latency" issue is not a problem with the MX-980 check the facts. I would like to challenge those who have a 980 and equipment to test with, to update their CCP software to the latest version and then download to MX-980. Take any/all base stations out of the picture. Set the 980 to either IR/RF or just RF.
I'm betting you will see the latency. You can further test this by changing the 980 back to "IR" only and you will see that the remote has very little to no latency what so ever. Again, take all base stations completely out of the picture when you're doing these tests.
If any of you determine that there is no issue then it's a hardware issue on a specific batch of remotes.