Shifted forms attack bonus

[Shhhhhhh]

When i'm shifted in any form it seems, my attack bonus on some attacks mysteriously drops. For example i'd have +35, +30 , +25 in a form, and would attack with those, but every couple of attacks i'd suddenly have an attack with +7 or +24. ( so for example 3+35, 14+30, 17+25, 12+35, 8+14)

Does anyone know why this is, if theres some way to avoid it, A shifter is still great to play, but it's just driving me crazy not knowing whats causing it.