@GlennH, what else do you have on your system? Remotes in particular - do you have a CCGX, Venus, DMC, or another remote? If so, have you confirmed that the MultiPlus is set to "On" on the remote? The front switch operation will be largely overridden by commands issued by a remote (with some exceptions), so the first place to check when experiencing this sort of thing is that 1. the remote is set to "On"; and 2. The connection between the MultiPlus and the remote is good.
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