http://en.wikipedia.org/wiki/Multitronic

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Reliability
Flashing gear selector (PRNDS) on the dashboard of an Audi A4, indicating a malfunction in the transmission system.

Despite its smoothness and improved fuel efficiency there have been numerous reports from owners around the world that the multitronic transmission is prone to electronic glitches and mechanical issues especially for models using clutch pack with six plates built before or around 2006.[5] Typical symptoms include flashing gear selector (PRNDS indicator) on the dashboard,[6] hesitation and/or shudder during acceleration,[7][8] unable to select reverse gear[9] etc. Although Audi recommends CVT transmission fluid change at 55,000 and 115,000 kilometres (or 35,000 and 75,000 miles),[10] there are cases that transmission failures still occurred even with recommended fluid changes.[7]

Class Action

In the USA a Class Action was won to give Audi owners a new transmission if it failed in the first 10 years . There are many ,many reports on web sites of failures . It is not a good recommendation by any means that at 150,000 kms your car just stops and costs you USD $7000 to fix and a weeks accommodation and meals to pay plus towing .