iPhone 6s Plus goes "no service" while using the Lightning digital AV adapter.

I'm using the Lightning digital AV adapter (A1438) with an iPhone 6s Plus and after few minutes the signal fades away and the message "No Service" appears. Connection to the cellular network is restored after the adapter is disconnected from the device. I have tried resetting the Network Settings and trying different hdmi cables. No luck.

I'm running on the latest iOS version.