ESXi USB serial device passthrough garbage data

[n_K]

Using ESXi 6.0, I've got an EFI based mac VM with VMWare guest additions installed - all working fine. The issue is however, I've attached a USB serial device to the server and passed it through to the VM, when I open the port I get garbage upon garbage upon garbage and lots of it (it's the same garbage being repeated over and over) as can be seen: http://pastebin.com/RBchgwCA

How the heck do I go about resolving this, if it can even be resolved? It's not an issue with the USB chip so it's either ESXi or the guest VM that's screwing it up

 

EDIT: I added it to a BIOS based windows 7 VM and there's no issues with garbage data, the input and outdata is fine and clean. Also tried with EFI based linux, the output repeated but it wasn't garbage data. Unloaded the apple kext and installed the manufacturer's kext, but the issue is still there albeit with different garbage data now.

Edited February 17, 2016 by n_K

[binaryzero]

Well for starters what you're doing is totally unsupported, so no wonder it doesn't work as expected.