@estadhouders if you use an id, ttyusb becomes redundant. In other words, even if it is on ttyusb12837, it should still find it, by serial.
But i guess that doesnt work, maybe you could look into symlinking it with udev.
See this page; https://www.sparkfun.com/news/2332
As for me, this happened when using a broken usb cable. It would cut it off and reconnect it.
