Be careful how you define your Backbone events.  When you are setting up an event such as:

this.someCollection.on('reset', this.render, this);

you’ll need to be very careful that you define this only once (ie in the constructor of the view … initialize) otherwise there is a chance when your view renders, it could created another duplicate reset event on the view, causing the render to execute more than once, leading to duplicates results in your view.

So keep in mind, the reset event should only get executed once, probably when the view is initialized.