BT audio is crashing the game for me if it's turned off in game.
I'm posting here if you have an issue with game suddenly crash at startup or crash in gameplay, it may be that BT headphones have to be connected for COTW to start again. Try starting game normally with last used BT headphones and if it starts OK then exit normally and then disconnect the BT audio. Now COTW should start normally again and you can use any other audio output.
You can also test this by turning off the BT headset in game (after you have saved the current progress by traveling to a tent or outpost) to see if COTW/Win handles switching audio output safely. Before you start testing crashes, do make a copy of your local Avalanche game save folder just to be safe.
If the game crashes you can (most of the times, not always) press ALT+TAB to switch windows and close the COTW crash sender and the game exits. If the monitor is just black and you can't close the crash sender window then press CTRL+ALT+DEL and select Task Manager, now you use ALT+TAB there should be "x" on the windows and you can close the crash sender and COTW window. If that doesn't work select Log Out instead of Task Manager.
I'm not certain if it is COTW or Windows or BT drivers that crashes the game and if it's COTW or the crash sender client that locks the system. All I know is that after every update of COTW this issue is removed or back again so I suspect COTW and reinstalling COTW (Steam version) does not help.
If you have the same issue please send error report in Zendesk together with your PC and BT-audio setup. This is an old issue and I have reported technical details in Zendesk last year and the year before and verified this issue with at least one other user on Windows 10 and Windows 11.