showing Hwy numbers and not street names

[mdsharp]

I have the TomTom ONE version 8.010 that I just got for christmas and have done all the updates. I ONLY receive maps that are official maps from TomTom and don't accept any user maps. I noticed that in the display 50% of the time the Highway number will show up instead of street name. For example in the display 20th street will show up as "Hwy 1175" instead of 20th street but 21st street and 19th street will show up. HOWEVER, when I am ON 20th street it will show "20TH street Hwy 1175" on the bottom status bar so I know the TomTom recognizes 20th street. I can also navigate to 20th street from another city but on the display it's shown as Hwy 1175 as I near it. I see no setting that say to show street names instead of Highway numbers in my change preferences.

Any ideas?

Michael