from the web*:
"..a found a setting in Advanced, its in the second section of advanced settings (Video) and it's called x264 CPU preset, mine was on superfast, so i changed it to fast, try that, i haven't tried it yet, but I'm going to, btw a message comes up if you change it saying how it could affect the stream, sorry if this didn't help :S.."
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http://help.twitch.tv/customer/portal/questions/8569428-getting-high-encoding-warning
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