Thank you for the suggestion, it is an interesting one. But I would prefer to keep everything in a single device (paired with Sabaj A20a amp) and sell the D30. I mainly use USB input and occasional Bluetooth, so easy or automatic input switching would be great.Topping BC3 is a Bluetooth receiver with LDAC that also has optical out. So you could connect it to the optical input on your D30, assuming you're not using that input already.
Topping BC3 Review (Bluetooth Receiver) & BT CODECs
This is a review and detailed measurements of the Topping BC3 Bluetooth receiver and headphone amplifier. It was sent to me by the online seller, Yaoyaotiger HIFI Audio Store and costs US $69. This is a follow up to our previous tests of Bluetooth receivers and investigating performance of...www.audiosciencereview.com
Of course if you're also anxious to upgrade your headphone amp, then the DX3 Pro+ could be a good choice
I do not have nor do I plan to ever use headphones.