Re: Public Speaker System - Am I missing the trick

@BillFlowerpot  You need to use a cheat to be able to change the type of music.  Bring up the cheats console (crtl-shift-C) and enter "testingcheatsenabled true" without quotes.  Then shift-click on the speaker and select the music type.  If you can't do it in live mode, try Buy mode: shift-click on the ground of the lot and select "Buy on this lot," then try it again.  When you're done, bring up the cheats console and enter "testingcheatsenabled false" to deactivate the cheat.

By the way, the option to build or buy on an unowned lot is also only available when the testingcheatsenabled cheat is active.