M 246 exposure jumping all over

[TheKidWantsTechno]

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Hello,

I've received a Leica M 246 a few weeks ago and so far very happy with it. I noticed tonight that if I pointed the camera towards a lamp the exposure jumps all over and the frame lines flicker. I haven't noticed it in daylight or any other setting so I'm thinking the type of light has something to do with it. It's a halogen light bulb. 

I tried to film it which can be seens here: 

 

If I cover the small round windows on the front, the exposure times jumping and the frame line flicker stops (not filmed).

Settings I've tested it with and tried:

ISO: Auto and fixed
Battery fully charged
SD Card: Formatted and tried different ones

Is this a failure or due to the light?
 

[overexposed]

I am not sure if the lines are auto dimmed when light changes, but that might be a reason