Why have I started to block the ball right?

[SirSliceAlot]

Just wondering if anybody can help. I have been playing golf for about 18 months and I am shooting, on average, 95-105, just so you know my standard.
I have always struggled with a bit of a slice/weak fade off the tee but other clubs have been relativly ok. Recently I have started to block or push nearly all shots from 8 iron up to the driver (which still slices). The ball sometimes go's almost straight right or a bit of a slice/fade right, often leaving me out of bounds or in the shite. I never play down the left hand side of a golf course!
I know my alignment, posture, grip etc is pretty sound (pros words not mine!) so I am guessing it has to be my swing. Somebody told me I might not be releasing the club properly or my swing is out to in, could anyone elaborate? Many thanks in advance.

 

[bobmac]

Sounds like clubface to me. Try moving your left hand to the right a touch and see if that straightens it out (right hander)

 

[SirSliceAlot]

'Try moving your left hand to the right a touch and see if that straightens it out (right hander)'

This is something I have tried Bob cheers. I have a pretty strong grip at the minute, ie I can see 3-4 knuckles of my left hand at address and it hasn't helped unfortunately!
Do you think it could be the 'release'? Do you consciously release the club like when you swing a baseball bat if that makes sense?

 

[bobmac]

If your grip is as strong as it is and your hitting it right it's then more likely to be a mental thing.
You cant release the clubhead back to square for fear of it going left so you over compensate by holding the clubface open.
Think of a baseball bat swing with a strong grip...left going left.
Have a chat with your pro again and ask him if you should weaken your grip to neutral THEN get the release sorted.

Of course it could be the clubhead is open at address