External clock for EmmLabs

I have latest EmmLabs gear and found external clock connector on the back panel of TSD1 transport. But DAC2 doesn't have.
As I understand synchro signal goes through EmmLink from Transport input to DAC.
Has anyone expirience in using external clock with EmmLabs?
How it affects to the sound?
Which one is best?
Thank you in advance.
The DAC2 re-syncs the clock internally, so an external clock is pointless. That's how it eliminates jitter from USB sources. It reads the data into a buffer then outputs the buffer to the D/A section via it's own clock, ensuring accurate timing of the data.
In my case sound from computer using USB is much better than from TSD1 using EmmLink.
And I think if it is possible to improve by external clock.
Or may be power regenerator like PS Audio can also help?