Possilble Leaking roof - Help

[rhysduck]

Just been up the attic to find the Mrs' Nintendo and noticed a lot of condensation, wet boxes, and dripping water

Luckily we haven't had time to put more up there since moving in!

Here's some pictures:

Spoiler

I fear this may be a bit expensive

We've been drying a fair bit of washing in the house in the spare bedroom upstairs over the last few weeks... Could this be the cause?

 

[rhysduck]

How do I check? Don't know anything about roofs It's a Semi-Detached if that makes any difference.

Pics addded btw!

 

[rhysduck]

Have eave vents yes, 8 in total on the front.
I'll check the eaves for blockages, "seems" as if the insulation goes right up against the eaves from first glance.

Fingers crossed!

Have had a look outside and can't tell if I've got ridge vents or not.. Is it easy to spot from inside the attic?

 

[rhysduck]

I've checked the soffits and I don't have rectangle vents but have the circular ones like these:
http://www.ebay.co.uk/itm/like/2513...&ff3=1&ff11=ICEP3.0.0&ff12=67&ff13=80&ff14=95