I’m on Cubase 12 but here it sends Song Position Pointer messages whenever the Project Cursor is relocated or Stop is pressed.
None of the MIDI Clock preferences needs to be checked.
I also tested with MIDI-OX.
Ah, I got it! I was analyzing this further, trying to answer your questions, and I discovered that it is the “Always Send Start Message” setting that disables the sending of SPP messages.
The MIDI Clock protocol has a Start message that starts the song from the beginning, and a Continue message that starts it from the Song Position Pointer.
I guess they figured if you’re going to start it from the beginning all the time, there’s no point in sending SPP messages, which makes sense.
I just didn’t take the time to understand that setting and checked it compulsively.
I honestly don’t know what the “MIDI Clock Follows Project Position” checkbox does. The Timing Clock messages don’t seem to change looking at them in MIDI-OX when I check that box versus when I don’t.