Connecting new (Thunderbolt 3) MBP to an audio interface

My new MBP doesn't seem to connect to any of my audio interfaces. I use it for live music. I have a Resident Audio Thunderbolt 3 interface but I had to get a Cable Matters TB3 to TB2 adaptor (only available in the US) and always connect it in a certain sequence to make it work - and even then it only worked some times. I also have a Motu Traveller which is FireWire. I need two expensive adaptors to connect them and again it only works sometimes. They both seem to choose the worst possible moment to crash, so you think it's working and then it lets you down. I've done some research and it seems there are no TB3 audio interfaces on the horizon but that a USB interface might be safer (with adaptors). I'm happy to get one but wondering if anybody can tell that it will work - or if anything will?