TomTom XXL 550 - can you stop the auto zoom feature?

I just received a 550 XXL, replaces a failed Nuvi 200W.

I like the unit so far, the only thing I don't like is that you can manual set a zoom setting...it automatically changes back. I like to set it so I can see the majority of the surrounding roads/features, but on a long trip; the unit zooms out and loses that detail.

Is there a fix? I can't find a setting anywhere to control this...