Try running the HTV Clean App if it is still installed on your HTV2 box. Seems to just delete temp media files and apk files.
I was suddenly getting these errors on my live app Extraordinary TV on all channels I tried-Yue Gang, CcTV and BinFen, ran the app and my free space increased to about 600 mb free. Now I can stream live tv again.
Let me know if this fixes any issues.