Welcome to Android Central forums. You don't mention what you've checked or tried so forgive me if I suggest things you've already looked at or tried.
Frist can you tell us what exactly updated? The system OS, the Android Auto app, a security update, Bluetooth or one of your players? Or is this just what you suspect given the sudden occurrence of this issue?
When you say that, something has affected your BT slider, do you mean the volume indicator for BT with you touch the volume rocker? Is it all the way up, down, or somewhere in between? I don't think this has much if anything to do with your issue because you are still able to make calls, and use Maps. If the volume was off or the cause neither of these would work either. That is, if the slider you're talking about is the volume slider. Additionally if the volume is maxed, which most would want it to be in this situation because it makes the sound your getting sound better if the volume is controlled by the stereo vs being low on the phone and having to max out the volume on the stereo to hear the audio.
Have you checked your actual BT settings for the connection between the phone and your car? You can access this in multiple ways, but the easiest is, while connected to the car, pull down your quick settings interface by dragging two fingers from the top of the screen, pressing and holding the BT icon until your BT list is displayed, then touching the car connection's name. Do not touch the toggle, touching the name will open the specific settings for this connection. Are calls and Media both toggled?
Have you tried forgetting the connection between the phone and the car, and trying to pair them again? I don't really see this as an issue because again everything else works except the media apps you've named. However, this is a quick and simple step and there are cases where the connection is the issue.
What happens when you attempt to play media with those apps you mention? They act like they are playing but you get no sound, the sound plays but plays through the speakers but it makes all of the sounds come through the phone speakers, like the BT has been turned off, or only the media sound comes through the speakers, all other sounds come from the stereo. I know you kind of answer this in your post but I'm just verifying we understand.
Have you tried any other apps? Have you tried playing YouTube, Instagram or any other media type apps to see if it is only those apps or if it is all media apps? Maps I do not believe is considered a media app, and calls are obviously calls.
Have you looked at the settings in the apps you're having issues with? Since you've been using them it would be easy to overlooking at the app settings themselves for changes. Look for anything related to headphone or BT playback.
Let us know what you find and tell us anything else you've tried that I may not have mentioned and we'll go from there.
Thanks for the in depth analysis Vid.Junky. Apologies it's taken so long to reply -Im a self employed tradesman and don't get masses of free time to spend on these types of communications,most of my out of hours time is spent on business admin!
I'll attempt to answer each question and at the end give you an update.
1)Q. what exactly did I update?
A. Android system update + periodic apps updates (as and when) + always restart device after any updates.
2) The Bluetooth slider I referred to is the media one. Whilst using Google Maps this slider was locked closed and also the "do not disturb " circle with dash through it is displayed. From this happening it feels like Google has free reign over your phone's connection preferences whilst you are driving. I want to navigate and listen to streaming or DAB and make/receive calls. I can only navigate and receive calls for whatever overriding preference Google is pushing (it seems)
3)Q. Volume slider?
A. No, this works as it should. My car multimedia volume control is as a percentage of the phones volume slider so you can never accidentally go louder .
Since this period I had taken your advice and un-paired the phone from the car, forgot the connection then re-paired the two. This after a recent Google services update seemed to rectify the"in car issue"
Worryingly things have developed into problems with the phones connection to the internet. The phone is a couple of years old now, however the transition between using home WiFi to access the internet then switching to 4G when I leave the house was always seamless. Now it's not..If I have the phone connected to the WiFi (usually whilst charging overnight) then switch to 4g when I leave for work it shows the 4G with 5bars with an exclamation mark next to them (instead of the upload and download data arrows)
Next I get a notification from the Android U.I that Talkmobile ( my carrier uses Vodafone UK) may be out of data - the icon on the phones top taskbar is a ghost 5 vertical bars with a question mark next to them.
(This a bit of a red herring as I have an active data manager App with a live overview of data used and have yet to exceed the 25gGb per month allowed)..
When you open up the notification again it's G STATIC on the head taskbar and "Access denied" on the web page.
I had assumed the above was linked to Android Auto but this is away from the vehicle with Bluetooth off.
The "fix" seems to be Settings- reset options - reset network settings then restart the device. Once restart has occurred I still need to get the phone to connect to my carrier manually and switch the "use data" back on before 4g connection is restored.
The above is more and more frequent. If I am out of data network coverage for any length of time, when I do return to a data zone, the phone won't connect without me having to perform the above-mentioned reset.
Likewise if I use the phone on WiFi anywhere where the data coverage is poor I can't assume that it will switch back to 4g when I expect it to, it's now 50/50 chance!
It's getting so frequent (at least once a day) I'm thinking of taking the SIM+ memory card out, dumping all the caches and hitting factory reset.
I'd appreciate if anyone knows just why this is occurring.? It's very frustrating and it feels like those controlling the network are deliberately impeding my access.
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