cannot record the ustream video continuously in specific channel

[ChoRyuJin]

I was trying to download the following livestream, it only becomes on air at specific schedule (in JST, look at the schedule)
record: http://www.ustream.tv/channel/2-5d1/
schedule: http://2-5-d.jp/schedule/

However, it can sometimes detects 720p, sometimes detects 240p. It actually broadcasts in high quality, 720p. I can only download 720p videos in 5 seconds only and then it can't record anymore.

In the past, it can be recorded but starting from this year it seems that it doesn't work. It may be something to do with the social network connection. Actually, when it becomes on air, I have to connect with SNS before I watch the channel from the official website (e.g. on May 19, 2015 20:00 JST, this page: http://2-5-d.jp/color-code/ will become ustream page embedded) However, if I access the ustream page (http://www.ustream.tv/channel/2-5d1/), I can still jump the SNS authentication step and watch the channel directly.

Is there anyone can help to check the errors?
Recent on air schedule:
May 18, 2015 20:00 JST
May 19, 2015 20:00 JST
May 21, 2015 20:00 JST
May 23, 2015 18:00 JST
May 24, 2015 18:00 JST
May 25, 2015 20:00 JST
May 26, 2015 20:00 JST
May 27, 2015 19:00 JST
May 28, 2015 19:00 JST

Thank you