Spellcasting being interrupted

[Intricus]

My level 18 mage has all his spellcasting skills maxed out at 95, including channeling which is supposed to help you get spells off even after taking damage, however, my casting is still constantly getting interrupted by every single hit I take. Is this normal? I seem to remember around level 10 or so being able to take 2 or 3 hits and still get spells off