The cavities may differ in size, mode and shelf layout. Equal temperature settings do not make their loading conditions identical.
What the observation means
A tray that fits comfortably in the main oven can restrict space in a narrow tall cavity. Its own cooking chart should guide shelf choice and quantities.
A useful next step
Record which cavity produced the changed result and use compatible cookware. Do not force a broad tray into the tall oven or remove supports to make room. If one cavity changes under its usual approved arrangement, that is a specific repair observation rather than a reason to adjust every oven.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.