Does anyone else regularly see blank token errors with the GoTo app?

Every few months we will have issues with the credentials for our GoTo app steps on campaign canvases.  When you configure the step and try to save you see a blank token error.

Every time we go to the overall app configuration and add a new credential with the exact same login and password.  We use that credential on the app step on the canvas & all is well again.

Does anyone else see this?  Anyone know what happens and how we can avoid it?  It's a minor issue, but it would be nice to prevent the main Eloqua users from seeing errors.