Changing settings on many interfaces (CSI, eDP) will cause an interruption in the transmission of the video data (the device immediately halts). Most connected SoCs at a minimum will report this as a transmission error, and may go into a frozen or faulty state. It is recommended to either change settings before starting transmission, or halt transmission first, before changing spread spectrum settings.
Especially in systems where initialization is done in several phases and video output has to be active before the complete initialization is complete. Spread Spectrum configuration must be done in an early phase.