as stated, i have a Garmin Edge 830 and a Garmin Forerunner 255
My 830 had an button issue and was replaced few weeks ago
I use the 830 mostly to follow MTB tracks i download from comunnity, so it's really useful to get audio turn by turn navigation alerts trought my bone conduction headphones, so i dont have to look to the unit every single turn
Since it was replaced (i think that it's since then), i stopped receiving Turn By Turn navigation audio alerts, and coincidentally Lap audio alerts (pace, heart rate etc) from my Forerunner 255 also stopped working, and it worked before
It's driving me nuts, as every option is selected, on both units