Question / Help Inconsistent Bit Rate Causing Major Stuttering - FPS or Other Issue?

Hi everyone,

So over the past little while, I've received increasing comments in chat that my stream is buffering or has stalled for a bit. I could confirm this by looking at my bit rates within OBS and dropped frames. However, I never noticed the amount of stuttering and how unbearable it actually was until I started watching my VODs recently. In fact, I could trace back this issue since early May!

Symptoms:

  • At a bitrate of 3500kbps, 720 downscale from 1080, 60 FPS, x264, actual rates have gone as far up as 5000, and low as <1000 (per OBS)
  • Screenshot of current OBS settings: http://i.imgur.com/gQPNnp3.png
  • OBS logs for such a stream: https://gist.github.com/abc0fc4280ec4b56326bbd1354c46531
  • Dropped frames counter per OBS goes up when live (if I had to estimate, over a 4 hour stream, about ~8-13% dropped frames)
  • Frequent stuttering noticed by viewers and within VODs
  • Results of tests with TwitchBandwidthTest (tests were run twice. Results are inconsistent and different every time): http://i.imgur.com/irL4IBY.png
  • Past 4 Twitch Inspector graphs results of 2 test streams and 2 actual streams at the above OBS settings (highly inconsistent bit rate): http://i.imgur.com/FEyIPcj.png

So I've been troubleshooting since last night:


Questions

Some helpful folks over at the IRC helped me determine that streaming at 30 FPS (vs 60 FPS) personally, caused slightly less issues.
An explanation I received from them for what I'm experiencing was that my connection is sensitive to changes in bitrate.

From their further explanation, I've watered it down for myself, as I don't really understand the technical aspects of streaming (hopefully I understood correctly), is that at 60 FPS, I'm trying to fit too much info at my bit rate of 3500. As a result, I have major fluctuations in bit rate to compensate. At 30 FPS, my bit rate can fully sustain and support the amount of data transferred.

  • Any recommendations as to how I can not use this workaround (of streaming at 30FPS) and stream at 60 FPS instead?
I just find it odd that looking through some old threads and posts, that people recommend streaming at 720p/60FPS at bit rates similar to mine without issue - I've seen recommendations for as low as 2500kbps.

From the explanation I was provided, it would make sense that increasing my bit rate would solve streaming at 60 FPS, but I highly doubt that all these individuals are partners and have access to very high bit rates. Clearly, 720p/60 FPS should be possible - I'm just not sure what my personal barrier is

  • Despite having "less" trouble when streaming at 30 FPS, it's still troubling that I have no consistency in results from TwitchBandwidthTest - Any clue as to what may be causing this?

TL:DR: OBS shows very inconsistent bit rates. Extreme stuttering on viewer side during streams (and VODs). Improvement (marginal) at 30 FPS vs 60FPS. TwitchBandwidthTest never shows consistent results with various servers. Tried a bunch of troubleshooting steps - starting to tear hair out.

Thank you in advance!
 
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