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I can't figure out how to prevent my iPhone SE (iOS 10.2) from vibrating when messages arrive while I'm on a call (that is, it vibrates right into my ear). This happens regularly, and I'm sure it occurs with other models/software versions.
I cannot find any setting regulating this, therefore it looks like a major bug: it doesn't have any function and interferes with the normal phone usage.
Does anybody know if anything has been/is being done with respect to this issue?