Is the CD7000 connected to CD on the MCL2AV ?
And is the LX5500 connected to TV on the MCL2AV ?
Did you try [AV] [CD] ?
It is possible to select the MCL2AV connections with a key combination:
To select CD press: [AV] [SHIFT] [RADIO] [7]
To select TAPE press: [AV] [SHIFT] [RADIO] [6}
Use the key combinations above without [AV] If you have speakers connected to the MCL2AV
But if your CD7000 is connected to CD it should automatically select that connector.
Maybe your LX5500 should be in option 1.5 ( [PICTURE] [1] [STORE] , [PICTURE] [5] [STORE] )
and the MCL2AV in option 1.6 ( [LINK] [1] [STORE] , [LINK] [6} [STORE] )