Randomly losing FFB

Hi everybody,

I have a SC1, small Mige. It always worked flawlessly, since I bout it, 2-3 years ago. However, recently, I am experiencing a recurrent problem:

On random occasions (maybe 1 or 2 times in an 1 hour race), the FFB sudenly becomes loose, as if going in understeer. This happened on straights, so it cannot be. Sometimes this only lasts a few tens of a second, other times it can last for longer that 1s. Not only the FFB goes loose, but also it does not seem to register steering input either. Then it goes back to normal, to maybe not happen again until the end of the race.
It happened in ACC, AC, iR so it’s not sim-related. It sounds similar to the reports in this thread.

I am running firmware 1.0.22, IONI 10716
Any help is much appreciated (did anybody else experience this?).

To me, this seems like some sort of USB interference issue.

Can you check if there are any USB related events in the debug event log right after this has happened?

I did not know about the event log - I will be sure to check it next time.

Also, now that you mention this, the only “change” I did lately, was to attach a small USB 4" display (using it with SimHub). Moreover, I used some small Neodymium magnets to removable attach it. Could this also contribute to the problem? :grimacing:


That USB screen could cause issue if its chassis was grounded to the motor somehow via the magnets or the button head bolts visible in the picture. It would form a ground loop that could cause the issue.

The screen/USB are isolated in a 3d printed plastic enclosure. The magnets are only in contact with the lower 2 screws (the screws are also not in contact with any electronic at the interior).

But I will give all this a try, at least I have a lead to follow. So thank you for taking the time to reply.2021-01-31_121038

I have saved this log file, not sure if it will tell you something or not.
sc1_log.txt (6.9 KB)

Some type of USB issue just before you started Simucube Configuration Tool:
“USB stack was reset due to being stuck busy : -1”

Thank you Mika. At least that should confirm that it’s not wheel related, but USB related (which is a good news :slight_smile: ). I will take the USB devices out one by one, and see what happens.

Try to get the Wheel on its own USB controller if possible… i.e. not through a hub or on a different protocol than most or all of your other devices… If the LCD screen is a USB display it is possible that it is hogging the same bandwidth that the Wheel is using so getting those on different controllers would probably be key to solving the issue.

Yes, I am currently testing this option. Over on Simhub discord, I was also suggested the bandwidth as a possibility.

I was not running it through a hub anyway (in fact I don’t use any hub on my PC), but I did changed it to another port, in any case. Will monitor in the next days and see if it behaves.

Even though items are not on a hub it is possible for them to be on the same USB controller in the computer… Most computers these days have three controllers (maybe four) for all of USB ports… Generally there is one for USB 2, one for USB 3.1 and one for USB 3.2… the thing is it get the high bandwidth devices on separate controllers… You can also as a last resort choose to get a PCI USB card so that you are sure to be on a different controller.