I think Jamulus is fantastic. Have you thought about funding all your efforts ?

Jamkazam is a different model but they raised 100,000 USD by crowd funding (!)
I wonder if a large cash injection would assist you ?

Here is an extract from the email I received today:
"First, we’d like to say thank you very much for your support of our GoFundMe campaign here: https://www.gofundme.com/f/cy2fsq-keep-jamkazam-alive-amp-improving. With your support, we met our goal to raise $100K that we can invest into improving the JamKazam service for everyone."