Let us know if you solve the problem formatting the SD Card, I'm more keen to think that it is a network or power issue. Never happened to me but I suspect one of those issues.
Do you a have a firewall between your PC and the camera? Is the camera on the same LAN/subnet/vlan of the mobile phone? What transformer are you using?
Thanks for the quick suggestions, everyone!
TLDR: Fixed by flipping the breaker on and off. Complete troubleshooting details/steps of what didn't work below in case other people are curious.
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So, I formatted the card via the app. That didn't stop the "Video playback failed (245416)." error. So I dug out a T6 screwdriver so I could remove the card and check it out in my computer. In the computer, it looked like the card was full with a bunch of 263ish MB .mp4 files, but when you try to open them, the video software says they're corrupted, despite just having formatted it. So I formatted the 64gb MicroSD card in my computer (Ex-fat) and put it back in the
doorbell. At that point, the doorbell was saying something like "Storage Exception" in settings portion of the app, and it said the card needed to be formatted. So I formatted it and still wasn't able to playback the motion-detection clips that I made after replacing and formatting the card.
I brought the card back to my computer and it appeared like it was full of 263ish MB despite having just formatted (still unable to open on the computer). Thinking that perhaps the card was bad, I grabbed another 32Gb card from a different manufacturer and formatted that in my computer (FAT32) and put it in the DB1 because it said it needed to be formatted again (do these use NTFS? I'll have to check next time I pull a card). Playback of recorded files was still failing with the same error. I pulled the 32gb card and saw the same issue with the card already seeming full of 263ish MB mp4 files that wouldn't open/play.
I tried deleting the doorbell from the EzViz app and then setting it up again (which just had me take a photo of the QR code and confirm my doorbell chime settings- I suppose I should dig back through and make sure other settings are correct) and that didn't seem to do it either. Thankfully I hadn't tried to do a lot of customization of video settings with other
tools.
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Finally I bit the bullet and went to my circuit breaker to try and figure out which breaker had the doorbell transformer (of course I didn't write it in when I installed the doorbell back in January).
After cycling the power of the transformer, when the doorbell came back online it seems like it is recording and playing back motion detection PIR clips without the error message!
So the old adage of "Did you power cycle it?" seems to have done the trick in this case. I wish there was a button to send a reboot command in the app (can I use the reset button behind the faceplate? though unscrewing and removing the faceplate is even more work than flipping the breaker once you know which one...)
Now that it seems to be working, I'm curious what the files look like on the microSD card (did it fill it up already or are there only a few files to correspond with the few PIR clips that have been saved?
Also, it's interesting to see that the photo/screenshot for each clip appears to be uploaded to the cloud even if you're not storing video in the cloud, since the screenshots always have been visible even when no working microSD or even any microSD was inserted?
Also, I have not had issues with the live feed (suggesting that the network/wifi connection is ok, and haven't had issues with the camera restarting itself or freezing to suggest inadequate power supply over the past six months)...Although I recognize that many other people in this thread have experienced unexpected results that don't seem to make sense, when they've switched transformers, etc. These doorbells really seem to be slightly different compared to most other technology troubleshooting I've had to do.
All up and running now, time to add to NVR etc
