Hi, could you be a bit more specific ? Does it hook ? What HMD you use ?
In general make shure that the resolution is higher than 640×480, bc if you end the game with alt+tab or due crashing it will reset the resolution back to 640×480 which doesnt work(one eye not sharp/no 3d).
You can also try starting the steamvr client and other clients(in my case wmr) in advance.