I would not upgrade either before improving your sources. For HT, I would get a IFI SPDIF iPurifier to improve the jitter for movies from your Smart TV and Blu-Ray player. This will reduce jitter for Dolby Digital and DTS sound tracks. You will be amazed at how good movies sound with this.
Then, for 2-channel, I highly recommend the Synchro-Mesh reclocker and a Reference BNC cable between the Bluesound and your Processor. This will reduce jitter significantly, to 18psec.
Both of these upgrades cost significantly less than a new DAC or preamp.
Steve N.Empirical Audio