8+ black screen with spinning circle

[Italianblend]

tonight my 8+ got a black screen and had a circle in the middle. I was unable to reboot it. I tried find my iPhone and eventually, about 10 minutes later, it started playing the sound and the phone was normal again.

Is this a known issue or should I take to Apple Store?

 

[ApplePersonFreak]

I would do a restore first and if the issue persists, of course take it to Apple.