Consider the following two options. If you want proper trunk tracking, purchase a RTL-SDR as shown in the first option. This is also a much simpler approach.
1.
Buy a RTL-SDR for $29.95 (US). I recommend that you purchase your RTL-SDR from a reputable vendor to avoid buying the cheap Chinese copies. If you do purchase the RTL-SDR, you will need to install the Zadig driver. Here are two links to help you find the RTL-SDR.
Login to your account Where to Buy RTL-SDR RTL2832U DVB-T Tuner Dongles At RTL-SDR.com we sell significantly improved premium RTL-SDR dongles but keep our profits low and offer free shipping in order to maintain low retail pricing. We strongly believe that our V3 and V4 dongles are currently the...
www.rtl-sdr.com
2. Use your HackRF with SDR# and pipe the audio out to a virtual audio cable using the
VB-Cable application. Next, point the DSDPlus.exe application to the virtual audio as the input. I never liked this approach, so I can't help you any further.
VB-Audio Virtual Cable and App's
vb-audio.com