This (my favourite) post from Rob W also mentions it but does not answer all your questions, but see he has posted some more above which is a lot more detailed: https://www.head-fi.org/threads/watts-up.800264/page-247#post-17293040

I would say White is standard with Green a variation with very slow roll off at top, suited for High res files (or possibly it was DSD) , but works for all files. I use Green just to keep it simple.

If it works it works. I prefer Kabeldirekt (check Amazon) over the stock ones as recommended by Rob Watts and is cheap; https://www.head-fi.org/threads/watts-up.800264/page-247#post-17293040

In addition to previous post, here is my favourite summary post from Rob W the designer: https://www.head-fi.org/threads/watts-up.800264/page-247#post-17293040

Agree with their view, and this optical kabeldirekt from Amazon is a great option and Rob Watts himself has recommended it in the past and it is cheap...

That is an excellent cable as well based on reviews, unless that is the one not working, if so try the kabeldirekt.

@kawhia: I have the sysconcept and it is excellent. For an even cheaper cable try kabeldirekt which if i remember correctly even Rob Watts have recommended...

Thank you for posting, seems like a nifty device, will read a bit more. Please let us know if if you like it!

Mine does the same unless I turn it off/down using the remote so would recommend you use the remote to put it in stand by (this is what I do). The off button on the DAC I think was intended for people who wanted to charge it up to 100% for outside use after the charge cycle (it still remains in...

One of my favourite summary posts from Rob located here that I think to a large extent answers questions 1 to 3, but not 4; https://www.head-fi.org/threads/watts-up.800264/page-247#post-17293040 Hope of value until further info from Rob. Edit: The optical cable Rob refers to is spelled...

This post from Mr Watts is really good and summarises it (towards the end of the post, so optical with power bank for the M scaler seems like a great alternative to wave cables): https://www.head-fi.org/threads/watts-up.800264/page-247#post-17293040

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I could hear a difference between the supplied cheap optical cable in the box and the much better Kabeldirekt and Sysconcept, but cannot say I hear which is better between the 2 latter ones. So normally recommend the cheap Kabeldirekt for people that want to try. Lifatec may be better but have...

I would recommend you try a usb certified cables from a reputable brand that is not too expensive first. I have a Supra usb cable (too stiff but great sound). Others may give other examples but would not go over the top and save the money. Look into Supra, Kabeldirekt (check Amazon), or...