Gradual audio/video desync when streaming

Hello,

Desync between video and audio (include mic) of stream increase gradually.

This is sample VOD: NakWonCHOISynl - Synology DiskStation (about 26.89GB)

And infomations of VOD:
ffprobe.exe -print_format json -loglevel fatal -show_streams -count_frames -i "Axenix-20220324-210825-형제단 서약자들 Battle brothers.mp4"

ffprobe -v quiet -print_format json -show_format -show_streams "Axenix-20220324-210825-형제단 서약자들 Battle brothers.mp4"

{
    "streams": [
        {
            "index": 0,
            "codec_name": "h264",
            "codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
            "profile": "High",
            "codec_type": "video",
            "codec_tag_string": "avc1",
            "codec_tag": "0x31637661",
            "width": 1920,
            "height": 1080,
            "coded_width": 1920,
            "coded_height": 1080,
            "closed_captions": 0,
            "has_b_frames": 2,
            "pix_fmt": "yuv420p",
            "level": 42,
            "chroma_location": "left",
            "refs": 1,
            "is_avc": "true",
            "nal_length_size": "4",
            "r_frame_rate": "60/1",
            "avg_frame_rate": "1306402387/21773417",
            "time_base": "1/90000",
            "start_pts": 1170,
            "start_time": "0.013000",
            "duration_ts": 3378890310,
            "duration": "37543.225667",
            "bit_rate": "6003320",
            "bits_per_raw_sample": "8",
            "nb_frames": "2252589",
            "disposition": {
                "default": 1,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0,
                "timed_thumbnails": 0
            },
            "tags": {
                "language": "und",
                "handler_name": "VideoHandler",
                "vendor_id": "[0][0][0][0]"
            }
        },
        {
            "index": 1,
            "codec_name": "aac",
            "codec_long_name": "AAC (Advanced Audio Coding)",
            "profile": "LC",
            "codec_type": "audio",
            "codec_tag_string": "mp4a",
            "codec_tag": "0x6134706d",
            "sample_fmt": "fltp",
            "sample_rate": "44100",
            "channels": 2,
            "channel_layout": "stereo",
            "bits_per_sample": 0,
            "r_frame_rate": "0/0",
            "avg_frame_rate": "0/0",
            "time_base": "1/44100",
            "start_pts": 0,
            "start_time": "0.000000",
            "duration_ts": 1655737322,
            "duration": "37545.063991",
            "bit_rate": "130516",
            "nb_frames": "1616932",
            "disposition": {
                "default": 1,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0,
                "timed_thumbnails": 0
            },
            "tags": {
                "language": "und",
                "handler_name": "SoundHandler",
                "vendor_id": "[0][0][0][0]"
            }
        }
    ]
}

ffprobe -loglevel error -skip_frame nokey -select_streams v:0 -show_entries frame=pkt_pts_time -of csv=print_section=0 "Axenix-20220324-210825-형제단 서약자들 Battle brothers.mp4"

0.013000
2.013000
4.013000
6.013000
8.013000
10.013000
12.013000
...
37536.088000
37538.088000
37540.088000
37542.088000

Keyframe is almost 2 second, sometime 2.0001 second

As you see, duration between video (37543.225667) and audio (37545.063991) has difference about 1.8 seconds.
Viewer mention the desync they can feel about.

  • System is:

CPU: Xeon E5-2679 v4
Board: supermicro X10DAi
GPU: GTX 970
RAM: 32G
Capture board: Supercast U6T HDMI USB3.0 ( 슈퍼캐스트 U6T HDMI USB3.0 > 영상장비 | 스카이디지탈 )
Audio interface: SPARTAN CUE 110 ( http://audio-probe.com/en/product/audio-interface/spartan-cue-110/ )

  • Environment is:

XSplit: 4.3.2202.1126 (latest)
Platform: Twitch, web auth
Codec: x264
Preset: fast
Bitlate: 6000kbps
Mode: CBR

  • Etc:

There is no frame drop in xsplit status.

May I ask a question? Does any of these apply to your DAW/loopback/ASIO mic setup? If applicable, set the microphone to None in the xsplit settings and try adding an audio source (loopback) to the scene source. There are two other methods, so please reply if you have any questions.