See the first post. It talks about "Sessions" and there is a link to the complete command list at the end. Basically there are 2 ways to open a session - either "open j talk" or "ask j talk to ...". Once the session is open you can issue multiple commands until it closes on its own (differs depending on the device). After the session is open you do not prepend "ask j talk to..." to the subsequent commands so if you are doing that Alexa won't understand.
I am considering closing the session after each command to make it less confusing. So, you would issue commands with "ask j talk to..." every time. What does everyone think about this?
By trial and error I figured out the sessions/open/ask. I have found at least on my Echo that a session times out after 10 seconds, so "ask JTalk" is more expedient anyway.
I noticed a problem with the session remaining open if I issue multiple commands in sequence. This may be because of the annoying "unknown zone" problem. It seems that Alexa is able to resume only if I let JTalk time out:
1. Ask JTalk to Pause
2. Alexa:OK (JRiver pauses)
3. A few seconds later Ask JTalk to Play
4. Alexa: Current zone is unknown
5. Alexa: JTalk timeout signal (bloomp)
6. Ask JTalk to Play
7. Alexa:OK (JRiver plays)
So I wonder if having the JTalk session remain open is actually causing this inability to resume?