Firstly do you know for certain its running std boost (7-8psi)??

The 3 hoses from the amal valve go to

C - compressor
W - Wastegate Actuator
forget the last letter but it goes to the metering unit

The ECU should have had a seal on it so you would of known if it has been opened before iirc?

What are the letters on the chip?

the bleed valve would of been to run more boost. . so it is 'possible' it is/has run more boost before, could suggest either way that it has or hasnt been chipped before!

cant really say for sure if it is chipped, or what thenoises are. When do the noises occur? what revs/full throttle etc?

Imo - remove the bleed valve, refit amal valve and take it to a tuner/rolling road and get them to set it up properly.