1st Veroboard Project

[andy-h-h]

And you are definitely using a BC182L with the unusual pin out?   

[JMac26]

Buzz the grounds with the multimeter. One probe on the board, and then go round and check that you actually have the continuity that you think you have to the other points. It's ridiculously easy to get a dodgy connection when everything is connected up with croc clips, and that alone would be enough to explain the symptoms you're seeing, so I'm not really convinced that there's a genuine problem here beyond basic "half built circuit". I'd personally be inclined to measure wires for jacks in the enclosure and solder everything up and get it ready to be boxed. If it *still* doesn't work at that point then I'll admit there might be fault

Thanks, i've tried connecting the dmm black probe to ground and using the red probe on all of the components that go to ground on the schematic. All of them have continuity to ground. I've used this setup in the past without this kind of issue. Granted, there is usually some noise, but it's nowhere near the level of the effect and disappears once it is boxed up.
Should I have continuity through the capacitors? i.e one probe on each leg of the caps, because I don't at the moment. 

[antonis]

Should I have continuity through the capacitors?

Only for shorted capacitors..

P.S.
Capacitors block DC..

[JMac26]

And you are definitely using a BC182L with the unusual pin out?

Yes I believe so, it was in the kit from Bitsbox, when I search the component code it comes up with the correct data sheet with

1. Base
2. Collector
3. Emitter

[JMac26]

Should I have continuity through the capacitors?

Only for shorted capacitors..

P.S.
Capacitors block DC..

Ok thanks 

[JMac26]

Haven't got any further with this. I removed a couple of the caps and tested them out of the circuit. Also corrected the misplacement of the jumper and 47uf cap I mentioned previously. I attempted to solder up the jacks and DC power connector properly (no croc clips) and still the same issue with loud buzzing.

Do transistors that have overheated still make sound? Or produce unwanted sound? Struggling to figure out which component could be causing this kind of issue. There's no continuity between the transistor legs so I don't think they've shorted.

[ElectricDruid]

so not this circuit?

I checked the layout against the schematic that Duck posted (trimmed above) and it checks out. That's the one.