Hi Adam Szalay,
I have checked your site and it seems like the size of the video you want to upload has exceeded the Maximum upload file size set at your backend. You'll need to change this setting to higher value in order to upload the video. You can find the setting at: Backend > EasyBlog > Settings > Media.
http://screencast.com/t/SHwj4bnwOgF .
In addition, I also have inspected PHP setting of your site and it seems like the
upload_max_filesize only allows 2MB and
post_max_size allows 8MB. You need to increase these to a higher value. To do this, please consult your web hosting provider.
Please advise.