Pan and Orbit functions through middle mouse button aren't working correctly

[toppano.1850257]

hello everyone,
recently I have this problem with the middle mouse button in order to use the Pan and Orbit function. In a few words, as soon as I click the key, it seems to work for a millisecond (since I notice the orbit or pan logo instead of the cursor) and then it doesn't work anymore, as if the command goes blank. by the way, if I hold down the middle key and move the mouse very fast, the view moves very little and then the command works for that very short period of time. I tried to consult the forum to find something useful to solve my problem and I used some suggestions: uninstall and reinstall fusion, reassign the middle button to the wheel, update the mouse drivers, check on an online site if the middle button worked, change mouse. Unfortunately, none of these tips solved the situation for me. I've never seen this kind of bug in the 4 years I've been using the program, and I would like to point out that the wheel zoom works without problems to this day. The mouse I was using for fusion was a Corsair M65 but unfortunately I had to change it; now I'm using a Rat 8+ from Mad Catz.
Please help me; I can't work fluidly like this. Thank you in advice

[Phil.E]

Sorry to hear of this. I haven't seen it reported anywhere else, so it may well be a problem that only you or very few people are experiencing. 

Usually this means hardware. 

You mention what sounds like button customization, outside of Fusion. Is that true? 

What is the navigation scheme you are using in Fusion? (check Help > Quick setup)