How can i get info(time) of background audio?

Hi! I have audio app. For listening audio i use AVFoundationFramework and make it in background with info by MPNowPlayingInfoCenter. If user making segue to other screen the audio are playing. I want show him info about playing audio on this new screen. The most problem is getting current time of playing in background audio. How can i get it?

P.S.: Length of audio primarily equals to one hour.

P.P.S.: Sorry for my English...

How can i get info(time) of background audio?
 
 
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