"I've been seventy four" - what does it mean? Is it something about drugs?
Any context? Where did you hear it?
For the moment I thought he said: "I have smoked before" but it didn't sound so distinctly.

It's from the Mean Creek movie:
Marty: "Wanna smoke a birthday doobie?"
Rocky: "Sam doesn't smoke weed, Marty!"
George: "I've been seventy-four."
Marty: "Yeah?"
George: "Yeah, I... I've smoked the whole blunt myself. I hallucinated. There was a little blue guy on my shoulder tap-dancing."
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Hm... I think I didn't catch what he said.
He asked Milly then: "Have you been soaked before?". At least I think it was soaked what I heard.
So, am I right? Does it sound natural?
Was it

'stoned before'?
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No, there were not any ts.

slang. to soak - to drink alcohol - to bib
http://dict.die.net/soaked /

Here is that part. You can hear it. Please tell me what you hear.

That link doesn't work for me but Grammar Geek listened to it in your other post and has confirmed that it is 'stoned'.
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