I improved the deposit sensor placement a few days ago and so far no missed deposits. 

The jackdaws have gottten pretty used to having to look for bottlecaps around the balcony, I took the arm off the machine and just put a few behind the machine, on the floor and in planters on the railing.

I'll be taking a holiday soon and won't be around to provide caps and butts, so it will be a real test for them.