Hi.
I would submit that it culprit could be the C/S causing input fluctuations to the trigeminal-cervico nucleus (some people call it the cervico-trigeminal nucleus) which takes input from C1/2/3.
I have been treating headaches using Dean Watson's (SA Australia) techniques which have been very helpful for when the headaches are from a cervical origin. Sometimes, the cervical input "tips" the headache over the edge and so you will see headaches at "that time of month" etc when the extra input from the ormonal stretching of the arteries causes "confusion" to the brain as to where the sensations are coming from... Confused yet? I took a while to get it around my head!
As the the tinnitus, i am pretty sure that the muscles that move the ossicles are innervated by the trigeminal nerve...
I found an interesting thread when looking for the trigeminal cervical nucleus...
www.nvapta.org/showthread...hreadid=77
Perhaps Jerry Hesch could comment here???