It is the response that SofaBaton does not understand. As a result, it retries over and over again. I was able to eliminate this issue by inserting a Node-red instance between SofaBaton and Homeseer. I can now send a simple http command to Node-red like "http://IPADDRESS/office/light/off" and Node-red communicates with Homeseer and sends "OK" back to SofaBaton. Took a bit to figure out how to set this up in Node-red, but it's working great.

Thanks for the reply, but that video is a fairly basic device setup tutorial. Not really applicable to my scenario. If other WiiM Amp Pro users are interested, I do have this working now as a set of HTTP API calls. I'm using the reverse proxy service on my Asustor NAS to convert the SofaBaton http calls to https.

That doesn't make sense to me. The problem is that the SofaBaton itself believes it should still be controlling the TV and not the streaming device. How would a macro on the streaming device help that? I have found a workaround. I connected a set of passive speakers to the WiiM Amp Pro, so I no longer need to use the TV speakers.

I am making some progress...I think. I discovered the API calls under Wifi Devices. The Wiim Amp Pro has an API interface. Problem is, however, it only accepts http calls via port 443. The SofaBaton does not support https. It will only make an http call, so certificate acknowledgment becomes the issue. I can hit the WiiM via a web browser and get an 'OK' back with the commands I'm using in SofaBaton. So I've been playing around with http-https proxies. http-proxy on Node.js is the one I'm trying now. I've got it relaying http commands as https from the browser, but the SofaBaton commands are not hitting the Proxy using the exact same url command. Bizarre.