If the other S4 is fine, then you want to get this one exchanged.
Hello there,
I recently bought a Galaxy S4 (refurbished) and started using it yesterday. But today I recorded a video and when I viewed it i saw this purple (sometimes green or red) blur dancing around on the video.
This is what I know:
1. The blurs appear on both my front and my back camera
2. They are still there when watching the video on another device
3. They are also there in other resolutions, but I haven't seen them on the lowest ones and the second highest it appears only sometimes.
4. They are also visible when I have zoomed in.
5. They are NOT visible in the preview. When I am recording everything seems fine. The blurs appear when watching the video.
6. EVEN when I record in black and white the PURPLE stains apprear.
Wat I tried:
1. Restart the phone
2. A third-party camera app
3. Booting in safe-mode
4. Various resolutions
5. Clearing the cache of my camera app and restarting it
6. Saving the videos on my internal memory instead of on my SD
7. Googled a lot but could not find anyone having the same problem or the solution.
I hope you guys can help me.
Thanks in advance.

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