I imported the codeset for your receiver. The input codes are there. Might be a glitch in the app.

For an example. I have a streaming activity created. When I press the streaming activity my TV comes on switches to the right TV input(HDM1), my Shield powers up, my Yamaha receiver powers on and switches to the correct input(HDMI2). I am ready to go. All by pressing the Streaming activity one time. I never had to press a button to switch the source on either my TV or receiver.

I see several commands after the ones you listed. Among those are several inputs. Yes, I owned a Denon AVR and the source selection are individual buttons on the remote. The way the X1 handles source selection is in an activity. You don't need to push a button because the activity will do the switching for you. As long as the source list is created under the device the activity does the switching. You never have to push the source key on either remote.

17 input commands in the list for the 3300

They were when I imported the code set

In Quick search enter Arcam in the brand name. Tap the box 'Unable to get exact model'. Tap search. Tap I already know that, next. Tap PA. 8 different code sets will come up. Start with Option 1 and start pushing buttons to see which Option work the best for you device. If the Option works then Tap it works.

Someone on Kickstarter got it to work using an old non mesh router running on his Eero 6 in passthrough mode. Check the comments in KS. Not a perfect solution but if you have your previous router laying around its a workaround. Other than that Sofabaton has acknowledged the issue on mesh networks and are working on it.

Awesome!

Tap Activities > Tap the activity you want to delete > Tap Edit >Tap Delete the current activity at the bottom

You need to setup a list of sources for the Denon in the Source switching mode portion of the app. Load Denon>Tap Edit>Tap Source configuration>Tap Switch Sources with one click>Tap the plus>choose the sources from the list - you can trigger(make sure the Denon is on) each command to make sure you are getting the right inputs>Tap determine>tap complete Once you do that you create an activity which allows you to pick the devices and sources that make up that particular activity....ie Watch TV or Stream or Listen to Radio ..etc