I do not use Yamaha gear but offer the following suggestions.....It is unlikely to be laptop.....as other stuff is not working as well...laptop is only sending a signal so check that signal is present.....check mixer for input and output signals....it could be a prob with internal amp cutting out...or speakers cutting out...some speakers and amps have clipping limiters and cut out when output peaks above recommended level to stop them from blowing....possibly GAIN is set too powerful for mixer or speakers...It could be dodgy leads from mixer to speakers. Tip do not run mixer at full power this could be the cause. red lights indicating clipping are a no no.

It is just a process of elimination....if you have checked that laptop is working and sending out signal through phone socket and mic is working etc....the problem must be down to mixer/amp or speakers. check all leads connections and inputs and output levels...if all else fails try a decent sound system (LOL)
I use Mackie....it will run all day and night on full power and sound fantastic...never had a problem.

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