Sensor Behavior between Vive and Vive Pro

[RazerCicak]

Hi, I have noticed something.

I have 2x Vive Pro, 1x OG Vive 

When in tried to block the all the side sensor on my OG Vive, the Vive still tracking and no Grey Screen.

When I block one of the side sensors on both of my Vive Pros, it stopped tracking and grey screen. Same behaviour for both Vive Pros

putting my arm on the bottom of the HMD result the same for both HMD

All 3 HMD is using same Base Station config.

Just wondering if this is normal behavior for the Vive and Vive Pro. Or Both my Vive Pro have some sensor issue =(

Can someone with a Vive Pro try to block some or all of the side sensor / put their arm under the HMD to see if they grey screened ?

[HackPerception]

@RazerCicak - Newer SteamVR hardware tends to be a little pickier as the updated SteamVR sensor ASICs have different requirements due to their support of 2.0 basestations. I find that all 2.0 enabled gear (both from Valve, HTC, etc...) can be a little more sensitive to environmental reflections and sensor occlusion in general.

Also, 1.0 tracking is now 5+ years old and the algorithms are have matured more.