What do these messages in syslog mean (stops my trackball working)?

[Chris Green]

I have a Logitech wireless trackball that I use with my Acer Aspire
netbook running Xubuntu 12.10.  It works for quite a while (random
amounts of time) and then stops, the following messages appear in syslog
when it stops:-

    Oct 11 11:24:06 acer-aspire kernel: [ 7812.377726] uhci_hcd 0000:00:1d.1: >host controller process error, something bad happened!
    Oct 11 11:24:06 acer-aspire kernel: [ 7812.377751] uhci_hcd 0000:00:1d.1: >host controller halted, very bad!
    Oct 11 11:24:06 acer-aspire kernel: [ 7812.377781] uhci_hcd 0000:00:1d.1: >HC died; cleaning up
    Oct 11 11:24:06 acer-aspire kernel: [ 7812.378030] usb 3-1: >USB disconnect, device number 2

An identical Logical trackball works perfectly with Xubuntu 12.10 on my
desktop machine.

-- 
Chris Green