Reolink cameras may not output H.265 stream when in low resolution due to hardware limitations. H.265 encoding requires more processing power than H.264, and lower resolution settings may not provide enough processing power to support H.265 encoding. Additionally, H.265 encoding is typically more beneficial for higher resolution video, as it provides better compression and reduces the file size without sacrificing video quality. Therefore, Reolink cameras may prioritize H.264 encoding for lower resolution settings to ensure smooth video streaming and recording.