Call your LAPD Senior Lead Officer; tell them to enforce the LAMC code below. Tell them you want your request put in the rotator so all 4 shifts cite the ice cream trucks. Also, call LAPD Traffic Bureau and tell them you want enforcement. There are also California Vehicle codes they can enforce that concerns stopping in the street and vending from a double parked position; 22500 and 22455.

SEC. 115.02. PROHIBITION AND REGULATIONS.
It shall be unlawful for any person, other than personnel of law enforcement or governmental agencies, or permittees duly authorized to use the same pursuant to Sec. 103.111 of this Code, to install, use, or operate within the City a loudspeaker or sound amplifying equipment in a fixed or movable position or mounted upon any sound truck for the purpose of giving instructions, directions, talks, addresses, lectures, or transmitting music to any persons or assemblages of persons in or upon any public street, alley, sidewalk, park, or place, or other public property except when installed, used or operated in compliance with the following provisions:

(a) In all residential zones and within 500 feet thereof, no sound amplifying equipment shall be installed, operated or used for commercial purposes at any time.