The issue is to have your dog focus on what YOU want.
So he's barking at odd times...train him to bark!
Or "speak" shall we say?
Get yourself and him riled up so that he's barking sporadically. Say speak during all of this to try and get him to "bark." Then have a calm down time in which you make a word for it...such as "Hush."
When he barks with you saying "Speak" or "Bark" or whatever, instantly calm down. He should "hush." If he doesn't calm down, just stand there. Do nothing. Do not get angry do not get excited...do nothing. He will calm down. You can say hush, but only if you say it in a calm manner. Screeching it at him won't help. When he calms and you say "Hush", give him a treat. He will associate "calm" with a treat. You may want to do this away from your other dogs and distractions. It will take awhile, but has worked with all dogs I've worked with. The trick is to have them bark when YOU want them to bark. They enjoy the barking, so you do not need to give a treat when he barks.
So he's barking at odd times...train him to bark!

Get yourself and him riled up so that he's barking sporadically. Say speak during all of this to try and get him to "bark." Then have a calm down time in which you make a word for it...such as "Hush."
When he barks with you saying "Speak" or "Bark" or whatever, instantly calm down. He should "hush." If he doesn't calm down, just stand there. Do nothing. Do not get angry do not get excited...do nothing. He will calm down. You can say hush, but only if you say it in a calm manner. Screeching it at him won't help. When he calms and you say "Hush", give him a treat. He will associate "calm" with a treat. You may want to do this away from your other dogs and distractions. It will take awhile, but has worked with all dogs I've worked with. The trick is to have them bark when YOU want them to bark. They enjoy the barking, so you do not need to give a treat when he barks.