This is because your device only has one event and this part doesn’t seems to accept only one event.
for device in mousea:
asyncio.ensure_future(print_events(device))
or a very dirty fix:
for device in mousea, mousea:
asyncio.ensure_future(print_events(device))
If the community wants to take over, please do, as I am not going to rewrite this. This is not related to Volumio support.
You can also take a look here, but involves a lot of adaption: