We have decades of experience building audio streaming protocols around UDP, and it has generally been our first choice, but we also know that both TCP and UDP, when implemented properly, are suitable for high-bandwidth, high-quality media streaming, so it was worth undertaking an exploration of “the other side” to see if there was actually a reason to consider switching.
After a series of experiments and prototypes, and a detailed exploration of both approaches, we found that we were able to extract more performance and reliability from TCP, so we took it to the next phase and started experimenting with TCP in our alpha environment a couple of months ago.
UDP is what I was referring to as BROADCAST. I forgot the term but network BROADCAST messages in software are usually done via UDP. This type of message delivery is not guaranteed and can lose packets. So it looks like ROON was using UDP and switched to TCP in June 2017. I was wrong thinking they still used UDP. However, that is just for ROON.
The test I described previously shows me that ROON does not do a perfect stream today when something is limiting them on the network. The distortion I heard on a repeatable manner tells me that even with TCP something is going on that is giving a less than perfect stream to the DAC.