From what I can determine and see from reading these forums the PAC has several 'operating modes': [LIST] [*]Connected to CGATE via a PC [*]Connected to PICED via a PC [*]Not connected to a PC [/LIST] Now I have read somewhere that the 'run time' mode is the Not connected one. I have also observed on my PAC that, if I leave it in the 'connected to CGATE' mode, after a while it stops responding to scene requests and needs a reset which suggests a memory leak somewhere (although my very slow PC may contribute to this). I can understand that leaving it in PICED mode is a debugging one. Now it seems to me that leaving it connected to CGATE should be perfectly acceptable as it is then running as a PC interface. (It is an issue for me since my PAC is in the back of my server cupboard and hard to reach!) Has anyone any views or experiences? Thanks Mark