Welcome to hifiguides! The Fiio bta30 or bta30 pro should do the trick for you. You can use the coax out on the bta30 to the coax input in the D30. They both can function as transmitter or receiver. The regular bta30 runs $89usd and the pro $120usd, which would be about 65-90 pounds. They both support up to LDAC and aptX HD. For your use case the regular non pro should be all you need.
Turn your headphone setup into a home theater surround sound experience.
This is how i play with Bass Transducer on Bluetooth.
Dayton Audio BST-1 mount on Secretlab Chair
Run through the SMSL DA9 Power Amplifier (BST-1 requires 50w)
You will need a Bluetooth transmitter that can transmit to 2 Bluetooth receiver, The Fiio BTA30 Pro.
BTA30 Pro will connect the laptop or any source via USB C while transmitting out to:
A: SMSL DA9 Power Amplifier Bluetooth mode
B: iFi Gryphon Bluetooth mode (I’m using my headphone for this setup)
Now you’ll have your bass transducer moving and your headphone as sound.
Secretlab chairs are Highly recommended because you don’t have to screw mount it, just slot into the belt below tightly.
Watch your favorite concerts or movies.
Note: Bluetooth may have slight latency here with YouTube or any online streaming. Downloaded content however is fine. Not sure why.
*DTS X Headphone Software is recommended here. It replicates the spatial sound experience you get when listening to sounds produced by multi-speaker sound systems.