diff --git a/src/mame/drivers/apf.cpp b/src/mame/drivers/apf.cpp
index d82f3107ace..67cb9b78f0b 100644
--- a/src/mame/drivers/apf.cpp
+++ b/src/mame/drivers/apf.cpp
@@ -560,6 +560,7 @@ static MACHINE_CONFIG_DERIVED( apfimag, apfm1000 )
 	MCFG_CASSETTE_ADD("cassette")
 	MCFG_CASSETTE_FORMATS(apf_cassette_formats)
 	MCFG_CASSETTE_DEFAULT_STATE(CASSETTE_STOPPED | CASSETTE_SPEAKER_ENABLED | CASSETTE_MOTOR_DISABLED)
+	MCFG_CASSETTE_INTERFACE("apf_cass")
 
 	MCFG_FD1771_ADD("fdc", 1000000) // guess
 	MCFG_FLOPPY_DRIVE_ADD("fdc:0", apf_floppies, "525dd", floppy_image_device::default_floppy_formats)