Squeezebox Duet - digital mods - which are best?

I have a Squeezebox Duet receiver with high quality linear PSU which feeds a Musical Fidelity A1008 DAC/amp. I’m looking for the best option for modifying the digital stages of the Duet (the analogue and wireless stages could go as I don’t use them).
The two ‘moders’ which come up regularly are Bolder cables (US) and Audiocom (UK). They both do effectively two stages of mods for around the same price. The Audiocom mods use Bybee devices (which seem a bit ‘smoke and mirrors’ to me), first stage is upgrading caps and adding Bybee thingys, the second stage is upgrading one of the voltage regulators and rewiring the coax output and adding a new connector. The Bolder first stage replaces caps and rewires the output and replaces the connector, the second stage also upgrades one of the voltage regulators.

I’d appreciate comments/recommendations on these mods. Thanks.

I did a lot of reading on this very subject because I own the Duet and my music server has become my primary source. What I learned was very interesting, but not definitive. To address all of the issues, one would have to spend a great deal of money, enough money in fact that it would be prudent to by a new source altogether. You can start with a good external linear power supply, but I can tell you from personal experience that you won’t hear much (IF ANY) difference. You can beef up the internal components (i.e.: caps, power supplies and digital path) – you know how much that will cost you through Bolder. Once you’ve done those things, you still have the real issue of jitter (which the aforementioned mods don’t address).
Now, to deal with jitter, you can invest in an external clock like the “Pace Car.” Now you’re investment is approaching $2,000 and there is still the issue relating to the SPDIF interface. In addition to that, the Duet will only support up to a 48/24 sample rate. This is important if your music server is your primary source and you want to take digital to the next level. Higher sample rate is what separates SACD from Redbook; it’s also what separates Redbook from high definition digital files (i.e.: 24/96, 24/192, etc.). This is where the future of digital music is heading.
After learning these facts, I abandoned my plans to continue my Duet upgrades. For roughly the same investment I purchased the new Perfect Wave DAC from PS Audio. Now, I hate to come off as a mouthpiece for the company (I have no affiliation) – I’ve already left some posts about this product, but this product simply sounds better than anything I’ve encountered and it will function as a server once the forthcoming “Bridge” device is released later this year (In the interim, I will feed the PWD with my Duet). Another option for roughly the same investment (as the aforementioned Duet mods) would be the Transporter, but the PWD is in a whole different league.
I suggest doing some more reading before you invest any money in upgrades. The Duet is a fine product (I love mine), but it is what it is. There are other options available that will take you to a different level. Think of a true high-end music server. It’s very exciting.

Rollier, I hope you won't mind me interposing a question to 2chnlben raised by his post. I was considering buying the Logitech Slim Line Transporter until I read your post about the PS Audio Perfectwave Dac. I saw the Paul McGowan youtube video on this DAC and it looks fantastic. By chance, did you compare the Perfectwave to the Logitech slim line transporter? As you probably know, the Perfectwave DAC cost $3,000 and the Slimline device I have seen on sale for about $1,600. Do you have any idea on what the cost of the PS Audio network bridge would be?
Rollier -

I did indeed compare the PWD to the Transporter, as the Transporter was connected to the same reference system that we used to audition the PWD -we ran the Transporter through the PWD. There is a clear and immediate difference in resolution and, really, everything across the spectrum when switching from the Transporter’s DAC to the PWD. The PWD is in a totally different league. After demoing the PWD, I don’t see how any DAC at any price can be substantially better. Through July, you can trade in any DAC for a rebate up to $1,000. So, if you have a DAC that retailed for $1,000, or more, all you need is $2,000. The Bridge will run you another $500 when it is released. After much research, I found this to be the only realistic option for building a true high-end music server. There are other products on the market (DACs and transports) that offer exceptional performance that will also interface with a music server setup, but the PWD is by far the best that I have found in terms of price/performance.
By the way 2chulben PSAudio has in house tech that will convert your SPDIF digital out on your duet to I2S.
I think I am going to get the PWD also and maybe consider having my SB3 converted, of coarse the SB3 only does upto 48/24 and maybe I should just experiment with what I have until the Bridge is available with built-in jitter control around the end of the year.
You are right from researching the PWD I have not seem nor read a product that has the features/benefits towards the next digital generation and at the price point with the liberal trade-in, at present there is no other component can match this piece.
Enjoy music!
Indeed, Rick Cullen, Cullen Circuits, will be offering I2S mods (via HDMI). With the Bridge forthcoming later this year however, I feel this is a mute point. The mod may very well cost as much, or nearly as much, as the Bridge. If you go with the PWD the only real option for a server will be the Bridge. In the interim, I will simply use the SPDIF/Coax to connect my Duet to the PWD.
I can’t speak highly enough about the little Duet. It is what got me involved with music servers. It is a truly fantastic device that literally changed the way I listen to (and how I perceive) music playback. After living with the Duet-based server, I learned that a music server is the only way to go. The future of digital music is in server-based systems. High resolution music is already available from a variety of sources, and I believe there will be many more options to come. A good external DAC (even a $500 one, like the DAC-Magic) in combination with the Duet makes for really great listening. What is so exciting about the PWD/Bridge, is that it takes all of the conveniences and features of systems like the Duet into the realm of true High fidelity.
Remember however the Bridge downsize it is hardwired Ethernet.