FPS huge drop on equipped shooter weapon & using scope view

[ammarofficial11]

Hi guys, 

I'm designing a mobile game using invector shooter. Ive noticed that when player starts equipped both weapons below, Huge FPS drop will happened.

Weapon affected:
1)Assault Rifle 
2)Sniper Rifle

I've also had to turn off scope view for all weapons as it performance cost(FPS drop ). but since sniper really need scope. Ive got no choice but to enabled it.  please take a look at my video below. Any advice?

[Invector]

Does this issue also happen when using the default inventory UI?

[ammarofficial11]

I've discovered the root cause. After check with profiler, FPS dropped due to camera rendering from both weapons when instantiate into scene... my humble guess is because both assault rifle and sniper contain prefab ScopeTarget >camera(active). Since I don't need this camera at all, just disabled it,then FPS no longer drop.

Tried to compared the spike with demoscene.. there is no spike from rendering except a bit from PlayerLoop Scripts which identical to my scene as well. 

**FYI Invector, Ive noticed that latest update ShooterMobile Demoscene doesn't have 'Aim' Button and LeftAnalog Script is missing..