Static electricity. What is the RH in your room? I am experiencing the same as every year at this time. When RH gets down to 35% or so you must be very diligent in ridding your gear of static.

In addition to good brushes and cloths I use this: https://www.musicdirect.com/equipment/accessories/furutech-destat-iii-static-charge-remover/

New owner better have some strong floors. They are massive

I moved several hundred thousand dollars of new and used equipment out of my home in the last 2 years. I was searching for the best I can ultimately afford. I also decided to use an integrated amp and a DAC/streamer rather than separates. I ended up with a NEW Luxman L-509Z and a NEW Aurender A20. My main speakers are Harbeth SHL5 30th Anniversary I bought used. I also spent about $4K on Shunyata Venom-X cables. The sound of this system is outstanding. I listened to better amps/preamps and integrateds but even used they cost significantly more than the Luxman. The A20 is an amazing piece of gear. No other DACs or network streamers I had in house were as expensive new or used. Over the 2 years I made a nice little profit that covered some of the costs for these 2 pieces of NEW gear. I am likely to upgrade my SACD/CD player to a Luxman-D07X but I can wait for a bit and that will be purchased used, maybe. When all is said and done I will likely have $50K invested including my analog set up. Did I listen to gear that sounded better to my ears? Yes. However, I chose to pay the price for that gear new and I did not want to settle for used.

If you are willing to spend the money you likely will find something that sounds better. Some say at every $10K-$15K interval you should hear a distinct difference in the factors that ultimately define better sound. However, you must have the ears that can detect it. You will also need a properly treated/designed room. IMHO, if you can’t afford to spend more than $10K for a system you should focus more on room treatment as it will me a much bigger bang for the buck.

edit: My gear - https://www.reddit.com/r/audiophile/comments/1848qoa/i_have_almost_completed_my_end_game_rig/

Sound quality reproduction is very subjective. Additionally one must consider the gear used in your system as it is important they have synergy between them. Just as important, some believe even more important, is room treatment. A poorly arranged/setup room will make even the most expensive high quality gear seem lackluster even boring. With that said, here are the DACs/network streamers I owned. All also can be used as preamps.

NAD C658 - good all around device

Auralic Altair G2.1 - Overall much better than the NAD

Ayre QX-8 - Better than the Auralic but not the same quality gap as between the NAD and Auralic.

Aurender A20 - This one is on a whole other level than the Ayre. As is to be expected.

I have found no matter the gear, once you get above the $10K cost point per device the quality of sound reproduction is audibly better.

My opinion

Str-VT7 or VT6

Either is impressive. And much less than Pioneer or Marantz

Something else to consider is an excellent monitor (2 way design) and a well implemented subwoofer. Keep in mind room size and treatments are extremely important when deciding on speaker purchases. I highly recommend calling and talking with Frtiz Speakers. Start by reading information on his website and then call and ask questions. He is very helpful.

https://www.fritzspeakers.com/