Make sure the map CD is clean and the laser is clean

Slow nav performance is always caused by poor map reading.

Poor map reading is caused by weak/old laser, dirty/scratched disc, or deteriorated map disc

An original disc always works MUCH better than any copied disc, because the reflective layer is much more efficient on a stamped CD than a burnt CD. So you should use original discs if you have them...

Sorry, I don't think I was descriptive enough;

I have original maps from 2002, 2003 and after I upgraded to 3/1-63, I just bought new maps from BMW (2008).

The software worked fine up until the upgrade. After the upgrade, when I am on the input destination screen (the one that has the address (UNITED STATES, CITY, STREET ADDRESS, fastest route, Directions) ... to get to Previous Destinations, normally, I'd turn the knob once and the second half of the screen is shown (where I can select the Previous Destinations or something out of my Address Book). Now, when I turn the knob, I must wait approximately 15 seconds before the screen is shown. Likewise, when I select a previous destination, there is a 15 second delay before that screen is shown.

There seems to be that 15 second delay between each screen; that is, 15 seconds to retrieve my previous destinations, or to display my address book, or to select something out of the address book.

I'd like to downrev the software to see if behavior changes. What are the steps I need to take?

1. Insert older OS SW version eg 3-1/50
2. Follow instructions on screen