It was good that you pointed out Umer. There is no harm in that. Since its a public forum we have to help each other out as a community.
Good thing OP also got to know it now so he would be careful to look out for such things. I got my amplifier from the same person and thoroughly checked it for repairs or fake. So in any deal just be careful. Hasnain is a nice guy and I am sure he was ripped off too as he doesn't know much about care audio himself.
OP I suggest you let the previous owner know about it. No hard feelings, we just have to look out for each other