flashers

Turn signals aren’t working and emergency flashers button isn’t staying on I installed after market radio on 2004 rsx and the turn signals don’t work my flashers come on when I push the button but they don’t stay on unless I hold them.

Does anyone know what I'm talking about? Installed in line with the brake light circuit. Microprocessors or relays allows the lights to flash and then constantly on. Some are adjustable. This is different than just a relay, b/c it stops flashing after a while. I had this on my old car, but...