OK, more information direct from ASUS tech support by phone. Two calls today.
1st rep: Listens to me carefully, politely asks a few questions. Puts me on hold. Comes back and says: Bluetooth in the ME173X is looking to connect ONLY to other Android devices. Use a third party app to intercede and mediate between the two. Any suggestions for which one to use. No.
I doubted this but decided it's worth a try. Tried several (4 I think) BT "manager" type apps. All of them failed because the base BT capability cannot be launched without the process giving up.
2nd rep: Again, listens politely and asks more questions. Apologizes for rep #1's ill conceived answers. This time I fill in a small number additional details and observations I've discovered while experimenting, like in a limited number of times I cannot turn off BT after failure. The tab says "Connected" but the car says it's not. Then there are times when the car says Connected but the tab says disconnected. The majority of times though the connection only lasts a second or two then gives up. There were a few occasions when the "BT has stopped" appeared but surprisingly I can hear the music streaming. Unfortunately, because the error message is in focus your only option is to dismiss it with an OK and then it really does stop. Music dead. Leaves me on hold for about 7-8 minutes while he "checks on some things". (He's actually going to ask someone else).
With the BT in a failed state, we investigate more detailed settings underneath BT. There we're seeing "Car Multimedia" (the Subaru) is in a disconnected state. Over to the right, there's a settings icon. Tap it. This pulls up a subsequent panel showing among other things "Phone audio" with a checkbox and "Media audio" with a checkbox. Both are checked on. Let's try to turn them off and on again. Turn one off. This action clears the box but also greys out both preventing further adjustment. Restart the tab. Return to the same settings area and now I can turn Phone and Media audio on/off at will. So when this thing craps out, all BT functions are dead or nearly dead until. I asked if there was any way to restart the BT software module. There isn't - your only remedy is a restart - according to ASUS.
So we attempted to use BT with just one audio source turned on. Failed. Restarted and disabled the first and turned on the second. Failed.
So, after more standing by while he researches, the rep took a lot of contact info, assigned this a ticket number said that this issue will be forwarded to their engineering staff for a closer look. I told him I do expect some answer by eMail at least in the next week to 10 days. Again, nobody dies because BT isn't working so I thought that a reasonable settlement for this round. At this point, I'm waiting for a response and will pass that along here when and
IF ASUS comes back to me.
H