Discovery broadcasts are ignored by some minidsp apps

[mrene]

Found the issue. I searched for "3999" (the UDP port) in the Wi-DG firmware and found this in the Alexa client.

// UDP
var udpSocket = require('dgram').createSocket('udp4');
udpSocket.on('message', function (d) {
// If MiniDSP discovery packet
if (d[0] == 0x80 && d[2] == 0x05 && d[3] == 0xA0) {
var hwid = String(d[18]);
var dspNo = String(d[21]);
if (hwid != currentDevice.hwid) {
console.log("Device Found: " + deviceTypes[hwid] + ' : ' + dspNo + '.');
currentDevice.hwid = hwid;
currentDevice.dspNo = dspNo;
}
}
});

I changed the first 4 bytes of the UDP broadcast to "0x80, 0x00, 0x05, 0xA0" and it was immediately recognized by the plugin.

Not sure where the change needs implementing in minidsp-rs as I am using an ESP32 as a USB to WiFi bridge.

Originally posted by @minimaded in #575 (comment)