Not responding to click wheel

I have just replaced the battery and fully charged it. Immediately the iPod began playing from my music collection, but I can't stop it or change the selection. The click wheel doesn't respond at all, so I can't do a reset. Docking the iPod on top of my Pure radio amplifier it plays perfectly, but...

There is no reception from headphones.

The click wheel behaves as if it is disabled by the HOLD switch.

This leads me to think that the ribbon connector to the headphone jack unit with its many fine connectors was not re-assembled correctly. It fit underneath the connector block and is impossible to see. If this was not in place, it could disable both the headphone jack and the Hold switch, effectively disabling the click wheel. Apart from the swelling of the old battery, there is no reason to believe the click wheel itself is faulty. Any ideas please?