@DaveInDenver if you're talking about interference from another wireless winch controller, what's the range on these things? None of our nearest neighbors at home have winches (nor are their houses actually that close to ours up here) and the parking lot at work was empty except for my GX, my work RAV4, and one other RAV4/Subaru sized car whose owner was probably out walking a trail.
Expected reliable operating range in your case is probably around 50 feet and expected safe from interference range is probably around ten times that, 500 feet from other sources (meaning if you're 500 feet from all known devices it should be safe).
Thing is you're thinking just about winch controllers that might have been around but that's not the problem. If it was just ComeUp winches the chances of them interacting will be in fact very small.
You didn't ask, but the rest of the story.
Using physical distance on these shared bands is not a reliable way to prevent interactions.
I'll try to use some analogies to describe it. First, think of RF like sound waves. If you have a speaker producing sound, just a tone. If you're right next to it it's loud but gets quieter as you move away. But sometimes you can be 50 feet away and barely hear it, like when there's other background noise. But other times you can be 100 feet away and still hear it clearly, like at night when you're camping. The sound level produced is measureably the same but for various reasons your perception changes.
Now introduce a second speaker making a sound. There's two possibilities, one is it's making the same tone and the second is it's making a different tone. When they're they same tone right next to each other you couldn't distinguish which is which. Move them away until you can and you'll find it'll take a lot more distance than if it's two different frequencies. But even if they are different tones right next to each other they still blend and might interact very badly to make a third tone. So in either case the only way to really have aboslutely no interaction is a lot of space between them (you know, like the distance you want to put between you and the kid with his boom-boom car stereo).
That's not possible with RF, there's just too much of it now. You can try distance to prevent interacting with each other. So like the boom-boom kid you have to close your windows and put a pillow over your ears to get some sleep. But that's not practical nor really an option to have absolute silence without 40 acres. Which works fine if you can pull it off but there's 350 million of us here now so broadly speaking it's not really possible to spread us all out. Well, technically it is. But not if we want open space. So most of us have to live on top of each other and figure out how to co-exist.
Thus, like the living in the city RF has to be able to not interfere as well as be compatible with each other. The FCC version of this is to say a device has to be tested to stay on it's frequency and produce the amount of power it's allowed. And all other devices have to come up with ways to live with this. So the car analogy, a device has to have a muffler or stereo that is only some volume and all the other cars have to have windows and bodies thick enough that if another is more than 25 feet away you won't normally hear it.
Back in RF let's say you have two-way radios. If everyone uses the same frequency (e.g channel) on purpose but you can share the airwaves as long as everyone is courteous, waits their turn, listens, etc. If you have someone who ignores the protocol and just keys and talks whenever they want then everyone suffers. You can put a mile between them and you. That works sometimes, doesn't sometimes. You can put 10 miles between you and them, this will almost always work. If you can put 100 miles then you will never hear each other. Now say someone is using a lot of power with a device that isn't well tuned. You could be using two different frequencies but still interact. This is spatter in the radio world, being so egregiously bad that you don't run in your lane anymore.
Still, lots of things have to share frequencies. You can have dozens of cell phones in a room and they are all operating on the same frequencies but only one phone will ring when a call comes in, right? That's because cell phones have kinds of protocols that allow them to share airwaves and operate next to each other without issues. They have embedded in their signal an identification.
Another example of this is your computer on WiFi. It knows how to talk only to another computer on the same WiFi right? All the devices in your house are using the same WiFi channel but when you send a document to the printer your TV doesn't turn on.
That's where these winch remotes fail IMO. They pick a set of frequencies that have a lot of users, which would be OK but they use off the shelf protocols that are comparatively weak in protecting against interaction with each other with a lot of chance of spatter and inter-channel noise from poorly designed devices.
The winch controllers are the same as you find in people's audio streaming devices or security cameras or the dongle that turns on your porch light or whatever. In your case, assuming it's not a fault of the controller itself (which is a possibility) you would have to not only look for other winches but anything operating on 433 MHz. It could be literally anything, it's impossible to know for sure. A failing overhead street lamp might be making noise that upsets it.
There are better ways to do it but they are expensive to design and build. Using a different, less crowded band is one option. Using a better handshaking protocol is another.
I feel since the risk of injury and property damage is high enough that I would think of more secure ways personally. You might think of this as the difference in having no password on your WiFi. You can share the airwaves with your neighbor and even use the same channel with different names but only if you each have a different SSID passwords can you really co-exist without risk of them knowing your bank account balances.
But when you really boil it down is being wireless solving a problem you really have over a wired remote? Maybe it is easier but the risk/benefit is not properly vetted out. If it must be wireless then they should IMO use a method appropriate. They use wireless remotes for overhead cranes but the way they do it is much more secure. But the marketing departments know no one will pay $$$$$ for a system like that, even though they probably should.
The way ComeUp did this isn't very secure. It's actually probably fine in the backcountry but in town there's just too much RF pollution, it's a problem waiting to bite us. I don't like them at all but I would definitely disable it when you're in town.
All of this assumes there isn't a more fundamental problem. If you have a crossed wire that's exposed shorting then it wouldn't matter. You need to do the basics of good routing, good workmanship, good crimps, insulation, tightened screws. That's paramount. This RF stuff is a secondary step. As a cause it is a big assumption I'm making. But I've seen enough of similar weird issues, like a lawn irrigation controller misbehaving that turned out to be certain brands of RC cars as a source.
haha
. Pssst, thanks so much to my amazing, sexy, handsome, amazing husband who included in our vows to always be my pit crew 
. So don’t stress it. 2. His idea and my idea of organization are very different. Especially where he puts his tools and recovery equipment versus where I plan to put mine.
