First-half goals from Cauley Woodrow and Kevan Hurst did the damage for the Shrimpers, who have now won five of their last seven league games at sit nicely in the League Two play-off zone.
"I am an honest manager and I have got an honest bunch of players," Brown said. "They have responded to any kind of criticism with some fabulous performances of late. We have got three wins and three clean sheets on the bounce.
"If the players keep performing like they are doing then people will find it difficult against us. We performed with that bit of quality in the first half that got us the 2-0 scoreline but second half they did throw the kitchen sink at us but we stood up to it manfully.
"We have fallen upon a system that suits everyone at the club. Barry Corr couldn't make the starting line-up and Cauley got himself a goal. Both goals were from great crosses.
"Players are playing with confidence and it is making sure we keep hold of that confidence because it can be fragile in any division."