USB with preferences.. need advice

Hi...
I bought a used laptop in a shop for almost nothing. Which I am quite happy for since it covers all my requirements and i dont have that much money.
The problem is that my USB does not want to work with all my devices.

It is USB 2 and I have 2 of them in my laptop.
For eliminate confusion I will call one A and the other B.

My laser mouse will only work in A
My webcam will work in both A and B
My midi device has worked on the labtop but does not anymore. ( it draws power from the computer but is not used unless power supply is plug in)
My harddisk works both in A and B.

I find this very odd, I cannot return it but I can send it to repair, though that will cost me money if they do not find anything.

What should I do ?

Thank you and best regards..

 

Well yeah, I will try to supply my mididevice aswell, but that does unfortunaly not solve my problem.

When only having my mouse connected to a USB B and nothing In A it does not work.
I do get the Wondows found you hardware sound from WIndows. Bot nothing happends after.

 

I think you missed out half the problem man..
I need my midi device to work. !

But I think the best solution would me to get a powered Usbswish and put it in A... If anybody can see another solution please say soo and if you think my solution is the best please say so ...

Best regards