Is anyone having this problem?

Brand new Nexus 4. Telus Canada.

Every time I lock the screen and unlock it it loses the network. No service for about 20 seconds. Even if I lock and unlock right away, no service until it reconnects.
During this time I can't access internet or even reply to a text that just came in while it was locked.
I called Google and they said they will replace the phone under warranty. The service call was very pleasant.
I thought it was a software bug? Anyone else experiencing this?

Thanks