HLS Stream Fails on Roku but Works on Other Platforms.

Hi all, I'm facing an issue where an HLS stream fails to play on Roku devices, but it works fine on web browsers, iOS, and Apple TV. On Roku, the player shows the error: "An unexpected problem (but not server timeout or HTTP error) has been detected."

Codec used: avc1.640032, mp4a.40.2  

Subtitle reference: GROUP-ID="subs" and SUBTITLES="subs"  

Roku Model: 3920X

Things I’ve tried: 

- Matched subtitle casing 

- Confirmed no geo-restrictions or DRM 

- Validated playlist and segment URLs

The video still fails only on Roku. Has anyone experienced this or found a fix for subtitle-related playback issues?

Thanks in advance!