It's been a while since I took another look into this, but I have a lead that this forum could possibly help with. On a side note, the Arduino forum was not very helpful at all. The only thing that I could think of was if the Arduino was being driven too much power (or if the power is inconsistent somehow), and the switched I have in the dance mat are acting as capacitors and letting some current through. I haven't done any measurements or math to look into this, but it seems very unlikely to me.
Asking chatgpt, I got lead to check permissions of the usb device, and even giving the decide all permissions does not help. However, I decided to check the dmesg log, and noticed something. I am transcribing this from a photo I took of the text on a CRC tv, so I apologize if there's errors.
[ 153.053753] usb 1-1.1.3 New USB device strings Mfr=1, Product=2 SerialNumber=3 [ 153.053758] usb 1-1.1.3 Product: Arduino Leonardo [ 153.053763] usb 1-1.1.3 Manufacturer: Arduino LLC [ 153.053768] usb 1-1.1.3 SerialNumber: HIDAF [ 153.067997] input: Arduino LLC Arduino Leonardo as /devices/platform/scb/61500000.pcie/pci0000:00/0000:00:00.0/usb1/1-1/1-1.1/1-1.1.3/1-1.1.3:1.2/0003:2341:0036.0003/input/input4 [ 153.068204] hid-generic: 0003:2341:8036.0003: input.hidraw2: USB HID v1.01 joystick (Arduino LLC Arduino Leonardo) on usb-0000:01:00.0-1.1.3/input2 [ 154.009506] cdc_acm 1-1.1.3:1.0: ttyACM0: USB ACM device [ 154.092227] usbcore: registered new interface driver cdc_acm [ 154.092232] cdc_acm: USB Abstract Control Model driver for USB *[illegible]* and USB adapterA couple things I noticed here: The arduino is being read as an input into input 4, and it is being read as a HID joystick into input 2, and it is being read as an ACM device. Do any of you think that being registered as multiple inputs/systems could cause the issues I am seeing? And if so, how can I make Debian only recognize the arduino as one device? I am not linux savvy enough to know how to do that.
Thanks!