McCormack DNA-1 Gold or DNA-225

Get a non functioning unit and have it sent to SMc Audio. They will essentially remove everything and give you a new amp. 
There is one DNA-1on Ebay with a 'Make Offer'. Have the seller ship it directly to SMc. Pat or Steve will guide you through the upgrade process.
Bob

Good for you dyl71.
Steve/Pat are converting my DNA-1's to monoblocks as we speak.
As I said, he is going to remove everything, so whether it works or not, or a monoblock is not an issue.
I had the gold revision done a year or two ago, when I found another DNA-1-non working, I decided to go for monoblocks.
It is going to take some time. Steve auditions everything before he sends it out. In fact, he usually adds small upgrades as new things come his way. Just be ready to be wowed.
Bob

@mitch2 
Pat ( I don't know his last name) has been my contact since I contacted SMcAudio. I don't know about Kris, but maybe he isn't on the phone as much as Pat. Some folks are better at taking calls than others.
@hifiman5 
Yes, I got the amps back a while ago, but haven't put them to their paces, yet. I needed to have Bob Worzalla at Sound Anchors make me a pair of stands to hold my subs and amps (besides the McC, I have a pair of Atma MA-1's- for my winter listening as they get way too hot).
Steve and Pat knew I had Atma's and gave it their best go, given my budget.
I will post my findings when everything gets put together, which includes not only amps, but new speaker cables, and Equi+Core power conditioners.
Yes, I know I am ill.
Bob

I finally got my DNA-1 monoblocks set up and burning in as I write.
I concur with dyl71, the sound is very clean and holistic.

My only problem is that the Vandy crossover for my 2wq subs only goes to 22K ohms in balanced. I think I need a lower setting. When I get some energy, I'll try them with the RCA cables and RCA xover, which goes down a bit more. This will probably be a new post comparing my experience with Atma-Sphere, McCormack and Ayre.
Re: Synergistic
I recall Pat mentioning how much better the amps would sound using them. I can't remember which one- Red or Blue.
B

@slaw 
Yes, do call Pat, he can give the best info.
As far as replacing all the fuses, then yes, you should change them all out, if possible. Though even replacing just the AC fuse makes a difference.
The HiFi Tuning were his choice, but I recall this past month he said the Synergistic fuses were the way to go. Again, I can't remember which one.

And, my DNA-1monoblocks are back and running in nicely. -Definitely giving the Atma's a run for the money...
B