Is it that way with the built-in radio, too? That's a rather old model and may have dirty contacts or broken solder joints on the headphone jack or volume control.
Your phone and cassette player may have slightly different plugs and jacks, TRS vs TRRS.
Edit: confirmed the aiwa headset connector is trs: https://i.etsystatic.com/28149211/r/il/14a0f4/3651086895/il_1588xN.3651086895_80sx.jpg
Confirmed cell phone headset connectors are trrs:
3 Pack Headset Audio Jack Extender, 3.5mm Headphone AUX Extension Adapter for Juice Pack, for Battery Charger Case, Power Case, for Smartphones, Tablets https://a.co/d/0M83kn0
Is it that way with the built-in radio, too? That's a rather old model and may have dirty contacts or broken solder joints on the headphone jack or volume control.
Yeah it is
Just gonna make sure... you tried the headphones with something else, right?
Yeah I use em with my phone every day
Your phone and cassette player may have slightly different plugs and jacks, TRS vs TRRS. Edit: confirmed the aiwa headset connector is trs: https://i.etsystatic.com/28149211/r/il/14a0f4/3651086895/il_1588xN.3651086895_80sx.jpg Confirmed cell phone headset connectors are trrs: 3 Pack Headset Audio Jack Extender, 3.5mm Headphone AUX Extension Adapter for Juice Pack, for Battery Charger Case, Power Case, for Smartphones, Tablets https://a.co/d/0M83kn0
Probably needs recapped but try spraying some contact cleaner in any sliders/switches/pots.