Problem with UI Panel Color

Hello. Today I faced really annoying problem which I can’t solve by myself, cus I have no idea whats going on.

I am working on inventory GUI system and now I wanted to make Equipment window. Everyting is okey and working well, BUT! My Equipment pannel changing colors randomly by itself! O.o. I found that problem by accident. If I close Inventory Window, Equipment panel change color. Some screens from that strange situation:

Inventory Opened: screen1

Inventory Closed: screen2

Inventory Opened: screen3

Inventory Closed: screen4

I have no idea whats going on. There is no script for changing colors on Equipment Panel, actually, there is NO connection between Inventory & Equipment Pannels.

Can somebody help me solve that strange problem? There is problem if I use too many Pannels in one GameObject?

EDIT! Same situation is when I click on button for generate items to my inventory. Equipment Pannel change color after random number of clicks…

EDIT2! I could solve that by disabling Image component on StatsPanel: screen. Unfortunatelly now I don’t have that border. Now I just wonder. Why if I enable it I am facing with so strange problem?

Okey I found answer. There must be something with Unity standart assets. When I downloaded & converted jpg image into Sprite UI and put as background situation seems to be stabilized. There is no changing colors by that panel any more.