Hello and thank you for using just answer. A website I recommend you look at is www.lexus.letstalk.com here you can find information on phones/options. Most bluetooth phones will work on this vehicle HOWEVER not all bluetooth features for every phone are compatable with your RX and will not work properly. On this site you will see the best compatable phones and what features work with your RX and what features do not. If your phone is not on the list it has not yet been tested or is not deemed compatable by lexus. Let me know if you need further assistance with this issue.
As far as the ignition system, can you clarify "locks up"? Does the key not insert, won't turn to start, or won't release? Most common issue on this car is customers that grab ahold of the steering wheel to assist in entry/exit of vehicle and accidentally lock the wheel. The only other "common" problem is key quality issues (bad cut/bent/damaged/dirty key). If you have a valid repeat concern with this all you can do is continue to duplicate the problem for a technician at the dealer, they have the ability to contact the engineers and authorize any and all repairs needed to resolve the problem if it is indeed a true failure and can be duplicated.
This is a PAY site, even if you made a deposit we do not get paid until you click "accept" and any amount of bonus is always appreciated.Please let me know if I can be of further assistance and thank you again for using just answer!