I received a call from this number today, same story when you return the call. Just thought I'd let you all know it's still active.

I got a call from this today, same story called back no answer.

Someone from this number has called me 13 times since 14 Oct 2013 and not once left a message. I have tried to call back and it always rings out, no voicemail, no answer. I think they are debt collectors trying to harass me but its a number they use that you cant find out who they are.

if this was a registered business of any kind there would be voicemail to be able to leave a message.. as this is the second call i have received in 2 weeks and neither time a message left, both times i have called back and the phone has rung out, ic an only presume it isnt legitamate

called. no voice message left. called back phone rang out.

Referring to my earlier comment, it is quite possible that they are on the other side, and they are trying to help debtors.
There are legal avenues not in common knowledge that can give relief to debtors, and some companies specialize in facilitating debtors' access to those solutions.
In any case make sure that the people you are talking to are the people they claim to be.
If you have debts out of control research Part IX and Part X of the Bankruptcy Act before talking to anyone about it.

I tried to call them back 3 times, no answer.
They are some cowboys operating way outside the law.
Ignore them. If you end up talking to them make them identify themselves. Do not reveal any personal information, because there is no way for you to verify their identity. (Anyone can steal some info and come back to you referring to it. Giving them your details, will complete their record for stealing/selling your identity.)
Record the conversation if you can (you must tell them before you start recording), and under no circumstances acknowledge any debt. If there is any debt that you know of, let them take you to court, so you get the protection of the law. Debtors have rights, and a court case will ensure that those rights are observed. If you engage with them outside the legal system the consequences are unpredictable.
Most of these cowboys don't have admissible evidence of the debt, therefore they will never take a legal action, but they can harass you for years if you let them.

these ppl called me after 7.30pm last night when all my kids were in bed. what kind of business (a glass business apparently) calls at that time of night?!?!?!

Got a call from this number. No voice message left.