@HesNot, I got my 100R a few days ago and I am using a Sandisk Ultra 200GB ($49.99 on amazon...at least it was before the holidays, so I am sure they will be at this price eventually) and it seems to be working rather well, I have had no issues so far.
General thoughts so far:
1. When I first got it, I charged it up from the 52% when I got it. I played around with it on Monday night and I could almost watch the battery drain...I thought here we go. Reading though the Cayin i5 thread (it took me weeks to decide between the 100r and the i5), I saw that when people were having issues with the battery, AndyKong continually suggested draining the battery dead, then charging it full to 100%. So I did this yesterday and today at work I had the player on the whole day (9 hours) and probably played about 4-5 hours of music (mainly 24/96 flac files), screen was off most of the time....the battery life is still at 71%. So I am relieved.
2. Along with doing the drain the battery and fully recharge exercise, I also disabled just about every app on the player...this is OK to do...you are not deleting the apps and you can always re-enable them later.
3. I have been using the stock music app for now, but I downloaded poweramp and a few others that I have for my phone and tablet. I think the Music app uses a lot more system resources that poweramp, so it might start extra services, which will drain the battery more.
4. As far as sound goes. It sounds really good with my flc8s IEMs, not as good with my Momentums. I have not done any kind of conscious comparison with my Cayin n5, but from memory, I would say the 100R has less bass then the n5 (no EQ used). But in general, I am happy with how it sounds. I also have not done any comparison across music apps yet.
5. One problem I have is with volume control. Tomorrow when I am playing around with it, I will have to make sure I know what I am talking about, but it seems like with the Music app, you have to have the volume set to 90 to get a nice comfortable volume. I think I switched to poweramp for a while and you only needed the volume set to 13 or so...the only problem was it was almost too loud and you turn it down and the volume did not reduce all that much until you hit 0 and the volume goes away completely. I checked the gain setting (in the DAP's settings, not the Music app settings) and it was at high (not sure if this is the default or I changed it at some point during my playing around phase), so I changed it to Low1, and the volume was better at around 13 and it seemed to control better (but this might have still been with poweramp)...but again, I need to look into this some more.
Questions for all the experts:
1. Does anyone know how to lock out the volume knob? I can that if you have it in your pocket, it would be very easy for the knob to get turned one way or the other, which would cause the volume to be all over the place. So it would be nice to have a way to lock out the knob, so the player basically ignores it if it turns...I have searched too hard yet.
2. Does anyone know how to kill the Google Services if possible? I have found how to do it for phones and I think tablets, but not on this particular device.
3. Does anyone know what SVI Settings app is? Furthermore, is there a way to kill it.
4. Has anyone found a case other than the ones that are being sold from Japan yet? For a screen this big, I wouldn't mind some kind of flip case that actually covers the screen.
5. On some albums, when I am playing them, they will say 44.1Khz FLAC/48Khz PCM, is there some kind of conversion or upsampling going on here? All the settings I see, they relate PCM to DSD files and I have all upsampling turned off, I believe.
So, I have a few more weeks to decide if I am going to keep it or not...one problem I am going to have shortly is that I just ordered a balanced cable for the flc8s and this player doesn't have balanced output...and it doesn't sound all that great with the Momentums, these are my main listening apparatus at this point..and I don't want to be continually changing the cables on the flcs.
Oh well, I am enjoying playing around with it so far, it is a fun little device.
Thanks,
Z