I'm trying to change the call-waiting behavior of incoming calls on a UC560 to ring the phone base instead of using the standard call-waiting beep. When setting the DNs to "call-waiting ring," the phones do indeed ring; however, the current call is cut off and interrupted with a period of silence while the phone base rings. This is happening on a setup with both SPA504G and SPA525G phones.
Is this normal behavior? Ideally, it seems like the phones should be able to ring with no impact on the current call.