@Sealwind,

The LED lights should be more or less the same intensity when performing the same operation, but do change brightness when using voice assistants etc. Maybe it’s just a bulb issue or even the angle of view or other lighting in the room, but if you’re still concerned by it, then maybe video/photograph what you see and submit a Sonos system diagnostic report from within the Sonos App and note it’s reference and then contact/chat with Sonos Support Staff via this LINK  and see what the Staff can suggest to resolve the matter.

Edit: Just to add, I usually opt to leave my Sonos status LED lights switched off - which is an available option in their room settings (See Settings/System/SRoom Name]’