As far as I know that is normal behavior since there is only one radio in the Moto X 2014. The voice calls go over the 1xRTT network and the phone has to disable the 4G LTE network for the duration of the call. The only way to change it is if the Advanced Calling feature is added to the phone and neither Motorola or Verizon Wireless has approved that update.
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BillyG57 I can see how receiving this message can become annoying really fast. We will figure this out together. While we can’t turn off the message. Please turn off data, power off the device, and remove the SIM card. Wait 30 seconds, replace the SIM card, turn on the data and test it. Please keep us posted. http://www.verizonwireless.com/support/devices/knowledge_base.html/120039
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