Chart Scale Falling Out of Sync With Data & Grid

[mje]

Have any of you ever seen behavior like this? I have a series of charts which as far as I can tell plot data normally if they're not scrolling, but once the horizontal axis begins to move, the data and grid lose synchronization with the scale. For example, at first I have charts that look like this:

 

 

Notice how the noise spike is approximately at the 0.9 minute mark on the horizontal axis. However after about 40 seconds, the scale is no longer aligned with the grid and data.

 

 

Note the grid does follow the data. The behavior is perhaps better visualized in a video.

 

The code that updates the charts is really simple, I'm not fidgeting with property nodes or anything:

 

 

The VI in the middle simply extracts relevant data from the Data object that comes in as event data. The blue wire only contains state information so the the UI knows which data to extract to each chart, it doesn't contain refnums or anything like that which get operated on when the chart is updated.

 

Any ideas?

 

m