This might be something with the GM. I've not messed with the GM since an early beta release, nor have I tried this feature. Is it something you can replicate repeatedly?
I would recommend what was mentioned above by notating it to Apple. If by some chance its a fluke in that its not replicable, they may just ignore and move on. But if its something that they garner interest in, they may contact you for further info. Understand that as part of the pre-beta/GM EULA, when submitting the issue, info from your device will be transmitted to Apple for the purpose of diagnostics.