Multi-view puppets need a pair of Face and Lip Sync behaviors applied to each view's subpuppet, instead of at the top level of the puppet (where they default to), to get mouth/visemes to work in all the views. You can remove the top-level pair and select the views to apply the pair in the Puppet panel. The top level behaviors are shown in the puppet panel when you deselect all.
We're considering having this happen automatically when more than one "Head" layer is found, or perhaps specially-named views.
Could You provide step by step info on how to do it ?
1. double-click on the puppet in the project panel to open it in the puppet panel
2. select no layers, or click on the very top row of the layers list (above "Name") -- this then shows in the properties panel the top-level behaviors applied to the puppet
3. in the properties panel, click the "hamburger" menu for Face and Lip Sync and choose Remove Behavior
4. select all the layer groups in the puppet panel that have separate mouths and facial features -- these groups are likely all at the same level (e.g. Front, Left Quarter, Right Profile, etc.)
5. using the "+" menu in the properties panel, add both Face and Lip Sync to the selected groups
Note 1: you can skip steps 2 & 3 if you want to leave the top-level behaviors applied. If you do this, when doing step 4, _don't_ select the top group layer (often "Front") -- the top-level behaviors will find and control this group. The reason you might want to do this is if the Head handle is not within the groups. By leaving the top-level Face behavior applied, it will control that handle.
Note 2: this will all be unnecessary in Preview 4 -- the top-level Face & Lip Sync behaviors will control nested groups all at the same time.