Mark, I have the Ailunce HD1. For each TG you specify whether you want promiscuous or not. I've set it for the TG's that I defined on the repeater. It would be nice if you just defined it for the repeater, which may be the way your MD-380 is.
When people are talking it shows the TG number in a pop-up. Of course that is kind of meaningless to me since as I scroll through TG's with the top knob, it shows the Alias. Also, when people are quick on the PTT the pop-up never goes away so if I did try to join in, I'd more than likely be talking on the wrong TG.
The way it should work would be if you are listening to a talkgroup, and you push the PTT it should switch transmit to that talkgroup. Perhaps it does, I don't know. I wish I had another DMR HT to test with. (Birthday is coming up.

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