Very wimpy backstabs?

[Isilion]

I'm RPing an assassin who is now level 19 and in the underdark with Aerie (his lover) and Imoen who he saved ASAP
Recently i started noticing something weird, my backstabs almost do no damage, usually 49 or sometimes 55 or 61 damage.
It wasn't like that earlier, I'm fairly sure i've seen 70+ non-crit backstabs before.
Let's do the math:
lvl 19: backstab multiplier 6
STR 19 (thief from BG1 with 18 STR and used a tome there): +7 damage (not multiplied)
assassin bonus: +1 damage
staff of Rhynn: D6 + 4 damage
2H weapon style bonus: +1 damage
49 - 7 (STR) = 42
42 /6 (multiplier) = 7
7 - 1 (ass) - 1 (2H) - 4 (weapon) = 1
so basically I'm almost always rolling ones? 55 would be 2 and the rare 61 is 3
after trying and trying and trying i just can't do any high damage backstabs anymore, and 49 is far more common than 55 which is more common than 61. This isn't just bad luck unless I'm extreeeemely unlucky.
it is as if my damage roll is not a D6 but a D3, or to be more precise a D6 divided by 2 rounded down (with a minimum of 1). 50% of 1, 33% chance of 2 and 17% chance of 3

is anyone aware of a bug like that? and how to fix it? it's very annoying that the core mechanism of my character is broken

to make things even weirder, when i test my backstab on aerie or imoen i do get hugh damage damage.
and another odd thing this started AFTER i reached lvl 19 and during that lvl up it stead "backstab multiplier increased by: -1", which was very odd so i checked my character sheet and saw it was still 6

edit: after some more testing on Aerie and Imoen, I nearly always get 73 (rolled a 5 on the D6) or sometimes 49 damage, never anything else. what is going on???

---------- Added 3 hours, 35 minutes and 58 seconds later... ----------

the problem is more general than i originally thought
even with non backstab attacks, the game rolls nothing but 1s for damage
and 5s if i attack my own party members
tested with both my staff +4 and a short sword +2

and all 3s with a short bow with normal arrows, both to enemies at to party members

[Rawgrim]

How can you backstab with a staff? Don`t you need stabbing weapons for that?

[T2Bruno]

A staff is THE backstab weapon in ToB.

[Isilion]

Originally Posted by Rawgrim

How can you backstab with a staff? Don`t you need stabbing weapons for that?

ALL weapons usable by single class thieves without Use All Items can be used to backstab.
And like T2Bruno mentions says, the best backstab weapon in the game is the Staff of the Ram in ToB, that's why i went wit staves as my main focus for my assassin.
Also the Staff of Rynn +4 is relatively cheap and eary accessible which is a big benefit when you go free Imoen ASAP with a tiny party as i'm doing

[Rawgrim]

I don`t even remember that staff. Been quite awhile since I played BG2. Where do you get it anyway?

[Isilion]

it consists of 2 parts and is put together by Cespenar in your pocket plane
the staff +4 is dropped by the red dragon in watcher's keep and other part is dropped by Gomnir in Saradush.
Combined they form a +6 staff, with possibly the highest damage per hit in the game, D6 + 12 + D4, and a chance to knock the enmy back

[SlickRCBD]

You're thinking of the Staff of the Ram. Staff of Rynn is found in the Adventurer's Mart and IIRC is the only +4 weapon to be found in chapter 2 or 3.

[Isilion]

after paying attention to it I found out it is not only backstabs
ALL damage done by my assassin is as if he had rolled a 1
for some reason the bug disappears when i rest, but after a while it comes back

does anyone know how to fix it?

[T2Bruno]

Are you fatigued?

[Isilion]

i just tested it, and O...M...G you're right
it IS fatigue
this is embarrassing!
this is my 14th run through the game and i never noticed it
I always rest as little as possible, so in all my games i've been running around super fatigued, but i always assumed fatigue wasn't cumulative. i played IWD too and there it was clear that fatigued stacked because it simply became impossible to hit anything. In BG2 that was not obvious, I seemed to hit without problem even though my characters hadn't seen their bed in a few days. Does it stack quicker in IWD?
Because I assumed fatigue wasn't cumulative and I always played very fatigued, I had already ruled out without actually testing it.

I've always had penalties in all my games then. I guess you don't "feel" the penalties that much, but because I now play an assassin it is multiplied by 7. It was with my backstabs that i noticed something was fishy, hence the title of the thread.
I guess my current party setup is making it even worse than in my regular parties. I only have my assassin, Aerie and Imoen, all characters with 1 attack/round and mediocre THACO at best, so I rely on haste a lot more than otherwise.
I also didn't notice it on Imoen and Aerie because they tend to miss a lot anyway.
How much fatigue does haste give? 1 stack of -1's?
Is it known how quickly it stacks? 1 stack per 24h + modifications by CON?

Seriously I'm so embarrassed it's something so basic :s
Shortly before i noticed the wimpy backstabs I had been diseased and I thought it was maybe some weird effect from a disease which didn't reset properly after expiring, and that it kept lingering on.

Well I'm glad the mystery has been solved
I'll go hide in shame now

[SlickRCBD]

Sounds like you were fatigued both in game and out of game.

[Isilion]

Originally Posted by SlickRCBD

Sounds like you were fatigued both in game and out of game.

quite possible
i have the bad habit or errrm ... not sleeping
well, not a lot
it's now 04.29 at night here, maybe i should go to bed

[Yoshimo's Heart]

Originally Posted by Isilion

quite possible
i have the bad habit or errrm ... not sleeping
well, not a lot
it's now 04.29 at night here, maybe i should go to bed

Lol the game even warns you about this during loading sequences sometimes (remember that while your character does not need food or sleep, but you do).