Lighting splitter for MIDI input and audio output?

iPhone SE (2020). I have a MIDI keyboard whose output I can send via a USB-to-Lightning adapter into my iPhone. This enables me to hear the resulting audio via GarageBand or any other audio app. However, I want to hear the audio output through headphones, and the only way to do that is to plug the headphones into the iPhone's Lightning port, which is already occupied by the MIDI input from my keyboard. Is there a Lightning splitter that will enable me to use the port for MIDI USB input and audio output simultaneously? I know there are splitters available that will give me audio output while I charge the phone simultaneously. But will these splitters work for my purpose, or are they dedicated exclusively to charging? (I could of course hear the output through Bluetooth headphones, but there's latency that delays the response to my keypresses on the MIDI keyboard.)