Singxer SU-6 and bypassing signal to the DAC

Hi, I'm using Allo USBridge Sig into a SingXer SU-6 who's clocks and output are very accurate and clean. I feel (just feel) that the Topping D90 with its HDMI might just be a fantastic combination - I am struggling to find out if I can direct the SU-6 signal to the DAC (direct) as the SU-6 has better clocks etc. This might be a giant killer combo?

I think ?!?!? what I am looking for is a DAC that can be synchronous (let the SU-6 feed the signal and be the clock?) I think the Matrix Sabre-X could do this?

Any thoughts? As I am beginning to wonder if $5,000+ DAC's are all that!!! before my next and possible last DAC purchase.

Not sure I am being clear here either. Many thanks