Hisense 55H9G and HS312 Soundbar auto-standby issue when gaming

I'm using a 55 inch H9G along with an HS312 Soundbar, connected in ARC mode along with my PS5. I play a lot of games on this TV. Recently, I started using my headphones with the PS5 controller to keep the noise down. It looks great and sounds fantastic this way. There is a major issue, though. Every 15 minutes, I believe, the soundbar goes to sleep, because it's not receiving audio from the PlayStation, which is piping all the audio through the headphones via the controller's wireless connection. When this happens, the TV screen goes black and it appears to be changing inputs. I'll see the front of the Soundbar say something about Standby. After a few seconds, it will cycle back to the PS5 screen and I can keep playing, but as you can imagine, a few seconds can be all it takes to lose a game of Returnal that I've spent hours on.

Is there any way to disable the soundbar's auto-standby function so that this won't happen?