This might be, because you have connected the setop box using HDMI AND SCART.
Why do you have SCART? Remove the SCART and the delay is gone. (it is, because the BV7 wants to talk to the setop box via SCART).
If you have SCART because of the AUDIO channels for Masterlink, then you can either:
- upgrade the BV7 SW to the latest version and there is no need to have SCART anymore
- connect using a simple SCART with only the AUDIO wires (see wikipedia for wiring)
- use another AV/SCART, I think you are using AV1, use AV2 (this might help)
- use a SCART connector only with AUDIO cinch connectors and connect only AUDIO cinch cables to the setop box
- use AV5 with the cinch cables