It is very difficult and often near-impossible to diagnose complex problems remotely. This will be as frustrating for the customer as for the unfortunate who is trying to help them.

It is helpful if you give complete information – my rule is to ask:

1) What did you do ?

2) What did you see ?

3) What did you expect to see ?

You will understand why "it didn't fix the problem" is not helpful.

I suspect your problem is that you are trying to control the H9 from two different places – this will confuse it. Please totally disconnect your Tech21 from the H9 and see how it works.