When using Google maps for satnav, car volume controls do not work. So only one volume level available for the nav instructions. Works OK using other applications. Any ideas?

In general I am finding this car very occasionally does weird software things for no reason. Not very reassuring.

You can adjust it using the scroll wheel on the steering wheel when it is making a navigation announcement. If you do it at any other time it will just be the radio/media that gets adjusted. The display will show a different icon when you are adjusting the navigation volume.

Thanks. I'll try it, but I think I did this at the time with no success.