melee spell interrupt

[Kagatob]

Were you power leveled to the level that you are? Channeling should prevent inturrupts the majority of the time, esp. considering your skill should be around 100 at your level.
Also check the 1 dmg hits, are they bashes? Those will be twice to three times as likely (I forget the actual numbers) to inturrupt, and 100% likely if they stun you.