Review on Swann 4K 16-Channel Wired Surveillance CCTV NVR System with 8 Spotlight and 8 Dome Cameras, Color Night Vision, 2-Way Audio, 2TB Hard Drive (SWNVK-1685808D8FB-US) by Brion Pine

As a normal camera, it works perfectly. The two-way audio system does not interfere. There is such a lag between them that the person leaves before you can even say a word. And such a delay (20-30 seconds) that you never know what they said in response. We have 4 regular cameras plus these for business. The application keeps crashing, the update did not help, the idea is great, but some jambs can definitely be fixed. If you realize there isn't a great option, this is no different, just be patient. (Note: Android app is better than Apple app)