997 A/C pump noise, slight groan

[KI57TUS]

Noisy when A/C switched on, sounds like a dry bearing. worried that it maybe the clutch or an internal fault.

Any help or info would be good

[MinchCS]

If a groan /wail - rather than grinding - that is typically most noticeable around 1500-3000 revs it indicates low refrigerant levels.
Common symptom in 997s. Don't ask how I know...
Top up should fix it. And then you can go looking for the leak - probably front condenser, or junction in pipes just below back of driver's door.

PS if it is grinding / screeching then ignore me.