2004 Chevy Impala DRL (headlights)/Spedometer

First, my Daytime Running Lights only work during the day and when my car is in gear. When I shift into park, they go out and they also do not come on when it's dark out. I only have highbeams to drive with at night. All of the other controls from the combination switch on the column work fine, as do all of the other exterior lights. Could this be a bad light sensor in the dashboard? And if so, what is the specific name for this sensor (I can't find a name for it anywhere!)? Second, my spedometer sometimes "ticks" as it moves around the display and will "freeze" even when I'm braking and come to a complete stop. I've seen it read 55 even though I had slowed down and stopped without the needle moving at all. It takes a while, but it'll eventually work itself back down to zero if I repeatedly turn the ignition switch back and forth between Off and Acc. And it has happened a few times and maxed out more than once even though I was only doing 45 but the needle continued to climb. Any ideas what's wrong? Thanks for your help!