I was recently using one of those microusb charger adapters. Some no name brand from the local electronics store, and probably comparable to what you’ve got. It undervolts, under load, resulting in sync drop outs and introducing noise. The device I was powering accepts 5V-12V. I went to a 12V Netgear power supply (from some old abandoned network switch or router presumably…but in my mind, a more reliably built power supply), and the problems all went away.
Arcade power supplies typically have the ability to be adjusted, and that really is a nice feature, particularly when powering arcade hardware that has a wide range of specs and needs.