I don’t own a Duo Cam Doorbell, so I can’t answer all of your questions, but I think I’m able to address at least some:
This is the standard experience with Wyze doorbell models, at least in my experience, and I believe it’s why so many users choose to enable the VoIP option, because it’s one way to clearly differentiate doorbell button press notifications from all other Wyze camera notifications. From the app’s Home screen, tap Account ➜ Notifications ➜ Push Notifications ➜ Voice Over IP ➜ Voice Over IP Calls toggle from (off) to (on). When doing this on an Android device, you’ll want to pay attention to the note at the bottom of this Help Center article:
It’s kind of like granting permission for your doorbell to call your phone, and it’s my understanding that each user who wants to receive VoIP phone calls from the doorbell will need to do this on his or her phone (so your wife would do this separately).
Note that I linked to a Help Center article for Video Doorbell v2 because I didn’t see a similar article for enabling VoIP for calls from Duo Cam Doorbell specifically, so I’m assuming the new doorbell also supports this feature, because all three previous Wyze doorbell models do.
There are other ways to get a specific camera to generate distinctive notification sounds on Android devices, but those involve the use of third-party applications and are not native to Wyze.
Unfortunately, this is currently true for all Wyze cameras, and it’s one of the disappointments that I’ve voiced frustration about in a Wishlist topic:
Please feel free to visit that topic, hit the Vote button above the first post, and share your comments and/or use cases.