I thought of that. There are two problems with that approach. First, it's a very intermittent problem that only occurs sometimes, so the trick would be to catch it while it's happening and not when you go to watch a recording two hours later or the next day (by which point the problem has often disappeared for the moment, possibly because the LNB finally warmed up?). The other problem is that the backend software makes this a difficult task, since you can't just change the mux frequency and have it automatically applied to all channels on that mux. Instead, after editing the mux frequency you'd need to delete the channel, delete the service, and then rescan the mux, remap the service, and find the new channel. Also, when you say up or down by 10, isn't that a pretty huge jump? If a transponder is at say 3800, just to pull a frequency out of thin air, I would think that going to 3810 or 3790 would be too much; I don't know what how close to the frequency the tuner needs to be to lock but on a typical LNB but wouldn't you want to first try increments of 1 or 2, for example 3802 or 3798?
The other thing I have wondered is I sometimes see people touting these expensive satellite meters with digital displays that would possibly provide this type of information, and those are fine if you are a satellite professional that uses such an item several times in a week. But I have wondered if it would be possible to make a poor man's version using something like a raspberry pi and a USB DVB-S2 tuner, or even by connecting a UBS tuner to an Android-based tablet or phone and running an app, assuming the tablet or phone has an active USB connection and you can find an adapter to connect to the mini USB connector on those things. I am just thinking out loud here, I have no plans to try and build such a device, not that I would have the slightest idea how in the first place. But, last week I was talking to a guy I know from way back in High School who is now a ham radio operator and he was telling me how the ham community is embracing Raspberry Pi's and in some cases tablet computers to perform functions that in the past would have required some piece of expensive and/or complicated hardware device, and usually at a very significant cost reduction. So I am just throwing that thought out there, not expecting anyone to rush off and build something, but just planting the idea and if it's already been done, I apologize but I am unaware of any such thing.