Avid streamers shouldn't have to deal with excessive lag or dropped frame rates, but sometimes these glitches happen. Fortunately, there are a number of precautions you can take and tweaks to make that can help the health of your livestream. And whether you're on Twitch*, Mixer*, or YouTube*, there are a few ways to diagnose why you might be lagging so much.
Whether you're receiving complaints about your stream from other viewers, or you're noticing dropped frames through a broadcasting suite like Open Broadcast Studio* (OBS), here are some tips on how to reduce lag and fix the problem.
Check the server
Buffering issues can often be attributed to something as simple as being connected to the wrong ingest server, which is the server you connect to for streaming. Before you log on to Twitch*, YouTube*, or Mixer*, conduct a ping test to confirm you're connected to a server that's within proximity of you. Connecting to a server based in Melbourne when you're in New York City won’t elicit the best ping times.
Check that nothing is on in the background
If you're dutiful about backing up your computer files, or perhaps you continuously have a few cloud accounts on sync at any given time, try shutting that off before starting your stream to help free up bandwidth. Streaming takes up quite a bit of upload allowance, which is typically limited on broadband connections, especially compared to download speeds. Stopping those background processes will free up what’s available for when you’re live. It’s also worth checking to see if anyone also using your network is performing any bandwidth-heavy activities.
Check your internet speed
Broadcasting a video game commonly requires uploading both the video and audio in real-time. Sometimes it includes a second video of a webcam that's focused solely on you, plus whatever widgets you might have displayed in your streaming suite. You’ll need quite a bit of bandwidth to showcase all that in high quality and without any interruptions. In some cases, making that available is as easy as turning off any background software that's actively using the internet. But if that doesn't work, then the problem could be with your internet speed.
Check to see how your internet connection is faring using a web service like Speedtest.net* to analyze your current upload and download speeds. The upload number, in particular, can help guide you on how to set up your stream relative to your allowance. For instance, if your upload speeds hover around 5 Mbps, then that's how much data you can send at any given time. At this particular number, try streaming at a 1080p resolution at 30 frames-per-second first. If you're still experiencing buffering issues, then try dialing it down to a 720p resolution at the same frame rate. Uploading lower resolutions and frame-rates takes up less bandwidth.
While there is no one-size-fits-all standard for how fast your internet should be while streaming, you can tweak the settings until you figure out what works for your particular setup. In most cases, the lowest you can stream in HD is at an 854 x 480 resolution, so it is possible to do so with limited bandwidth allowances.
Keep in mind, a straightforward speed test might not always provide the best analysis of your upload speed. These tests are general tools used to analyze your connection’s overall health, as opposed to how you are interacting with Twitch*, Mixer*, or YouTube* specifically. Still though, if your upload speed is stumbling, that’s a very good indication that you need to contact your Internet Service Provider (ISP), and either increase your upload bandwidth, or work with them to fix the issue.
How to Run a Test Stream
If you’re still experiencing buffering and dropped frames in your stream even after checking your internet connection and adjusting your bitrate, try running what some streaming services call a "test stream" to help further diagnose the issue. This is essentially an empty broadcast, which lets you actively test the internet connection as you're connected to live servers. One of the benefits of running a streaming test is that it can help you determine whether your issues are related to bandwidth or bitrate, helping you better diagnose the issue.
This sort of test differs between streaming services, but in most cases it requires a bit of time to run the diagnostics. Twitch” and Mixer” offer specific tools to help you figure out what’s going on, while YouTube’s* test streaming approach is geared towards a more general audience. You can use a test stream to help test the health of connected peripherals, too, and whether the stream can see or hear you when you’re live.
Twitch* users have the Twitch Inspector*, which actively logs the health of your most recent streams. If you haven’t streamed in a while and there’s no data to pluck from, you can run a streaming test by placing a bandwidth flag after the stream key in an encoder like OBS. The flag will prevent the stream from informing your followers you’re live. Run the test for 5-10 minutes4, or longer to accrue more data. Internet connections can fluctuate, and it can take a moment before you notice instability. Alternatively, you can check the Twitch Inspector while you're running the test to view the bitrate measurements in real time. Pay particular attention to whether the graph dips, as this can indicate the health of your stream. You want the graph to look as stable as possible. Twitch Inspector will also list the number of the average bitrate of the stream in the lower right corner. If you need more help, the handy “Select an Issue” drop-down menu towards the top of the screen will guide you through many of Twitch’s* helpful support pages.
Note that one caveat of doing a test with the Twitch* Inspector is that it doesn’t catch errors in the frame rate since the stream is blank. Twitch Analyzer* can help with this, though it’ll require that your stream is public-facing for it to gather that particular data.
Mixer* users have a similar tool for running a test stream. However, it's only available for partner or developer channels. The feature won’t even pop up unless you’re under this classification.
If you're a partner, the feature is available through the Broadcast Dashboard in the main settings panel, under Test Streams, though it’s only limited to five hours of test streaming a month. You’ll see a bar pop up with a link to the stream once you enable Test Mode, though it won't go live to your followers. For those who aren’t partners, you can at least access some analytics on past streams to see demographic breakdowns and such.
YouTube's instructions for running a test stream are a bit more generalized. YouTube suggests running a separate speed test like the one mentioned earlier to measure download and upload speeds. Failing that, running an unlisted live stream is another way to test what the stream is like when you’re live, and then reading through the analytics reports.
When to Start Checking Your Hardware
If you've exhausted the options presented here to fix your lag, including streaming at the lowest settings, and you're still dealing with buffering video and dropped frames, then it’s time to start checking on your hardware.
It will also help to ensure your processor is cooled with an appropriately powerful air or liquid CPU cooler, and that your thermal paste has been applied recently, and correctly.
An excellent way to check up on the internals of your computer is to run a test stream while simultaneously running a diagnostics app, like HWInfo*. An app like that will give you specific metrics on important things to monitor like CPU utilization and temperature. Reference CPU documentation to see if temperature is within standard operating range. If it's not, make sure that you're cooling with an appropriately powerful air or CPU cooler, and that your thermal paste has been applied recently, and correctly. If you're seeing high CPU utilization, try reducing the encoding preset or consider a bump in your processor. We recommend a current-generation Intel® Core™ i7 processor or higher as the entry point for gaming and streaming simultaneously.