I can't really find any direct evidence about them being funded by Soros, and it appears that TYT actually did a video dispelling the notion.
However, the video was in 2012, and the accusations appear to be from 2014, although they were also present in 2012 apparently.
In TYT's video, they claim that Soros funds the media conglomerate that they are a part of, but that they send money to the conglomerate and do not receive any money from them (and added that they'd be glad to take anyone's money if they'll donate to them).
Additionally, when researching the articles talking about TYT being funded by Soros, I noticed that they didn't really provide me any direct evidence (such as financial documents) proving the statements. This seems like "That which can be proven without evidence can be dismissed without evidence", but I'm not sure, especially with the date mismatch between 2012 and 2014.
Did the situation change? Is TYT funded directly or indirectly by George Soros?
*1 An American political commentary web series
*2 An American political action committee