If the HAP does not challenge your vinyl, you might try reclocking the S/PDIF output of the HAP with a Synchro-Mesh reclocker ($599). It is likely the jitter of the output that is the problem:
http://www.empiricalaudio.com/products/synchro-mesh
Powered by the Dynamo linear supply and using the optional BNC-BNC coax cable it provides a truly world-class digital signal. Many customers use it with Sonos, Squeezebox, computers, Wadia docking stations, Apple TV and many servers. 30-day money-back , less shipping.
reviews:
http://www.empiricalaudio.com/news-and-reviews/synchro-mesh
Steve N.
Empirical Audio