Well, I find it extremely odd that you would have the same issue on three devices when no one else sees it at all.
Are you using the stock dialer app?
Stock keyboard?
Stock launcher?
Do you mean that after finishing a call, the screen doesn't turn back on? I've actually seen that a few times on my Nexus 5 running MM. I found that pressing Power a couple of times wakes the screen back up. It doesn't consistently happen, but it does happen. I'm unrooted, running stock Google Now Launcher, no screen protector or case. CPU-Z shows that the proximity sensor is working normally.
Stock everything. Odd you say? No one at all you say? Hmm, what do we have here? Has this issue been identified across several Android devices of the years, each with it's own set of causes? Tell me what "no one else sees it at all" means.
Same issue. Anytime I take the phone away from my face it stays black.
G1, myTouch(rooted), Nexus S, Nexus 5
I'm glad to see I'm not the only one experiencing this problem. I have a non-rooted Nexus 6 w/o a screen protector on Android 6.0. Seeing that it's not across the board, it might be related to a combination of apps or settings that may be causing the issue.
Similar symptoms experienced by others including:
1. Sometimes reverts to normal behaviour after a reboot, but soon reverts back. I'ts unclear under what conditions it reverts back eg. seems to be independent of the screensaver.
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