When I wrote to Tesla and asked that they escalate attention to this issue, they wrote back with several questions. One question was to describe the various scenarios I have experienced. So, I generated this list. Posted here for people's reference and comparison.
o Start a podcast successfully, play for a period, pause. Podcast resumes from where it was left. This scenario rarely occurs and probably occurs only if the car is not off or is off for only a short time.
o Start a podcast successfully, play for a period, pause. Leave car. Return. Podcast has returned to the start. This is the most common behavior in the past few weeks. When combined with the inability to slide the cursor to resume part-way through (described below), this is what caused me to mostly give up trying to use the podcasts.
o Start a podcast successfully, play for a period, pause. Leave car. Return. Podcast playback has changed to a different episode. This happened today at one of my stops, but does not happen often.
o Start a podcast successfully, play for a period, pause. Leave car. Return. Audio system has switched sources. This tends to happen with long periods between stopping the car and re-starting it, such as overnight. This also sometimes happens when I am listening to sources other than TuneIn, such as the USB stick.
o Try to start a podcast, encounter Loading Error. Episode cannot be started and the controls for Pause, Stop, Play, etc., are all inoperable. Click on a different audio source, or click on a different podcast. Play the alternate source for a few seconds, then pause. Switch back to the original podcast. Podcast loads successfully and plays.
o Try to start a podcast, encounter Loading Error. Episode cannot be started and the controls for Pause, Stop, Play, etc., are all inoperable. Click on a different audio source, or click on a different podcast. Play the alternate source for a few seconds, then pause. Switch back to the original podcast. Podcast still will not play. Skip to the next episode or switch podcasts, or switch audio sources. Come back another day for the intended podcast.
o Start a podcast successfully, play for a while, encounter Loading Error. Podcast episode cannot be played at that time. Switch sources or podcast.
o Play a previously started podcast. Attempt to fast-forward part-way through the podcast by clicking and dragging on the time track cursor. Cursor moves ahead but only in increments of one or two minutes. And cursor will not allow multiple jumps in a short period of time. Moving ahead more than 5 or 6 minutes requires one or two minutes or more, several jumps, and pausing between. If attempting to go ahead more than 10 minutes or so, it becomes impractical and I gave up. This is the second common behavior that caused me to give up on TuneIn. It became impractical to listen to a portion of a podcast, lose my place as described above, and then find that place again.
o New scenario today: When I was testing today to prepare these notes, I listened to one episode of “CarTalk” for 10 or 15 minutes (episodes are 60 minutes). Once I was past some point, I found that I could indeed fast forward successfully by sliding the cursor on the timeline. I suspect that the downloaded podcast had been cached so that the system could move me quickly through the stored file. (This is a guess.) I am not sure exactly how long I was listening when I reached the point at which I could slide the cursor normally.
o Start a podcast successfully, play for a period, pause. Player continues to play the podcast but displays the “Play” symbol. Leave car for a few minutes. Return to the car, find that TuneIn had switched to a different podcast entirely.
o Start a podcast successfully, listen for 10-15 minutes. Park and exit the car. Return to the car the next day. Podcast resumes playing the same episode from approximately the place where play stopped the day before. Time track starts from 0:0 even though several minutes have elapsed. The time graph shows only about 30 or 40 minutes remaining, but the episodes are 60 minutes long. After listening for a few minutes, use the cursor to move the point of play, find can move ahead, but cannot return to a point before the time when play started today. [New behavior seen only once, just this week.]