"Jack
I'll bring it up for investigation in our meeting this week. This has been a recurring complaint, although it obviously shouldn't happen.
When a race has finished qualifying and I go to live manage in the 2D viewer, the driver controlled KERS option tends to be de-selected lately. Before, it used to have its box always seclected and I would make sure to de-select it.The first time I saw it de-selected, I assumed my driver would not use KERS, however he did. The issue was resolved when I checked and unchecked the driver controlled DRS box.
Excluding that, I have never had a problem stopping my driver from using KERS.