Fender Deluxe 85 - Channel Switching

[Aberdeen1981]

Evening all,

Recently obtained this amp (lovely sound!) but note that when I use the foot switch to change channel, it flicks from channel 1 to channel 2, then for a split second back to channel 1 before finishing as it should of channel 2... !!

Also note then when switching to the boost channel, if I play a bassy note, it seems to flicker between the 2 channels for a split second again.

Any advice?

Thanks
Andrew

[Enzo]

Electriclly loose switch in the stomp pedal comes immediately to mind.