H.Q. has been hard at work investigating the bugs you Agents have been reporting in the field.
First and foremost, thank you for your work in the Enhanced Operative Division, supporting the game, and letting us know what things are going wrong.
Second, we are happy to announce that we have pushed a beta build that *should* fix the mapping issues for the Valve Index.
In your Steam client, right-click the game and select 'Properties'.
Then, select the 'Beta' tab.
Finally, select the indexsupportbeta option. No password is required.

The more Agents that report to H.Q. letting us know the results, the better H.Q. can continue supporting your efforts.
As for the sound issue in the game, as stated in a community post earlier this month, we continue to investigate.
Cheers,
H.Q.