I'm sorry that you are unhappy with my response.
As I said, it is very difficult to diagnose these pronlems remotely. It could be the card, it could be the adaptor, it could be your unit, it could be the software, it could be something you are doing, the mains power, etc.
For all these reasons, I choose to start with the card.
If it is difficult for you to find one locally, I can get hold of one and try it on a 7600 and then send it to you. This will take time.
It is quicker if you find one locally and try it, but if this is not possible I shall send you one and request your patience.