Amplify Optical to Directstream DAC

Hi. I got rid of my preamp and just using Directstream DAC. Happy with audio from JRiver on laptop. However, the volume is insufficient using the optical from TV (PCM) to DAC. I’m running at 100% on DAC. I thought the path would be to have an app on laptop that can boost volume using optical to usb connector ( (no optical on laptop). I tried JRiver to stream audio, but the lipsync delay is terrible. Is there a fast usb audio to dac app? I really don’t want to go down the path of another preamp.

I have a Sony TV and it has a sync function in settings. Not sure exactly where your issue lies given the description.