Yes. My equipment is all line of site. As I stated here and in other posts I noticed this when I switched from using an MX-900 to MX-980. On the MX-900 there is no latency at all and all the devices are set to both IR/RF.

On the MX-980 if I set the devices to anything other than IR I get the latency on all devices. As one would expect, I thought it might be RF interference on the MRF-350. That's what led me to take the MRF-350 out of the picture and see if the problem persisted. And indeed, it did.

When the 980 is set to both IR/RF and the MRF-350's power is unplugged, I get the latency. If I plug power back into the MRF-350 and set the devices to RF only I get the latency. I've verified that there is no RF interference on the MRF-350. No solid red LED lights or flickering LED lights on the MRF-350. I've also tried setting the MRF-350 to several different IDs.

If I set the 980 to IR only the problem goes away. Regardless whether or not the MRF-350 is plugged in or not. Again, I want to emphasize that I see none of these issues with the MX-900 controlling the exact same equipment.

If you do a search on remotecentral you will see that several other people are experiencing this same issue. One poster stated that on his 980 everything was fine until he updated his CCP and downloaded it to his remote. He can't recall exactly which update caused the problem but he thinks it was one of the last two.

It's also possible that this issue is related only to a certain batch of remotes. Which would explain why you're not seeing the issue on any of your remotes.

How old is the remote that you're using in house? For reference purposes I purchased mine on 4/19/12. We could compare serial numbers as a method of determining the manufacture date.

Mine is B580112 0100937

There's also another set of numbers under the "Win CE .NET 4.2 Core" label. They are:

00039-496-641-966
X11-15297

Again, URC has escalated this to their engineers so there must be an issue. At least with some of the remotes. Maybe the newer ones.