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The Status Overlay notifies about a Recording in progress.
Channel Buffer
The Channel Buffer status appears automatically next to the Recording info when it gets over 50 frames (= encoded frames). A high Channel Buffer usually means that the storage may not be fast enough. The Channel Buffer is also displayed in the just:in Engine Diagnostics window.
Recording in Progress with Error(s)
If errors occurred during a Recording which did not necessarily lead to a Recording stop, yellow triangles will appear and more information can be found in the Inspector or the Channel Log.
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If there is no signal the Channel View will be black.