19:45:52.771: Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 3 (0.2%)
GPU is reaching its limits.
Second attempt:
19:47:39.253: Output 'adv_file_output': Number of skipped frames due to encoding lag: 5098 (130.5%) ---> CPU OVERLOADED
19:47:39.253: Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 203 (3.6%)
Use SIMPLE SETTINGS.
Recording Quality Indistinguishable
Encoder NVENC (use your GPU to encode, not your CPU)
Format FLV
AND:
19:35:39.442: video settings reset:
19:35:39.442: base resolution: 1366x768
19:35:39.442: output resolution: 1920x1080
Do not upscale. you will get bad image quality
Better, record at 768p and use handbrake afterwards.
https://handbrake.fr/