iPhone 4 connects erratically

[A8Jas]

I'm sure this thread will meet with groans of despair, but I can't find a proper answer anywhere else on the googleweb so I think it's time to ask the A8 experts...

it's a 2008 facelift D3 with DAB but no TV. I think sw 51.4.0. iPhone 4 is up to date firmware.

I can sync either way (searching from car or from phone) but after a few days it no longer syncs automatically and the only way to reconnect is to turn off the iPhone bluetooth then turn it back on again. The car then sees it and connects automatically and will continue to do so for a few more days.

OK so it's not the end of the world but a bit annoying