The [ON/OFF] button in the MULTI I/O section is not lit in orange.

In the following cases, the [ON/OFF] button in the MULTI I/O section is turned off:

・ When no external FX unit is connected.
・ When the [MODE] selector indicator is set to [CH 2/CH 5] and the [CH SELECT] switch is set to [MASTER].
・ When the [MODE] selector indicator is set to [CH2/CH5], while the [CH SELECT] switch is set to a channel that's set to [MULTI I/O] with the channel section input selector switch (CH2 or CH5).
・ Other situations where a feedback loop may occur depending on the combination of [CH SELECT] switch and the channel section input selector switch settings.