[App_rpt-users] Problem with node connections

Hi, Recently, one of my nodes has started playing up for no apparent reason! All of a sudden, when an incoming connection comes along, Asterisk quits and gives the following message: channel.c:1258 ast_channel_free: PBX may not have been terminated properly on 'IAX2xx.xx.xx.xx Outgoing calls to the same node seem fine but incoming still causes this problem! Can anyone point me in the right direction please as a Google search didnt turn up any helpful answers! Many thanks, Matt G4RKY