About X10 battery problems: After 2 years the battery of my X10 inflated to the point that the print was squeezed and I could NOT use the back and option buttons anymore.
So what to do now? As I know the power supply is very important for good sound quality I was considering the following: I never use my X10 dap while walking or cycling.
I mostly use the dap on a table in the garden with a JBL sound box or with a Koss headphone. Sometimes I use the dap in my car on the AUX input. But very often I use the X10 as an input for my hifi stereo system. Especially with high res 24 b 96k FLAC files this dap does not give any glitches or dropouts and is much better and more quiet (fanless) compared to my Sony Vaio laptop with external Musical Fidelity USB DAC.
Therefore I decided to make a major change to my X10 DAP as follows:
1. I removed the defective battery and cut off the connector including the power lines one by one in order to prevent short circuit.
2. At Aliexpress I ordered 2 NCR 18650B Li Ion batteries with a battery holder and a charger for a total of ca EUR 10,-
3. I mounted the battery holder to the back plate of the X10 with 4 small bolts M3. And I made sure the bolts were not too long because they should not touch the printed circuit board.
4. In the battery holder I switched the batteries in parallel. Thus I have a voltage of 3.7 V and a capacity of 2 × 3400= 6800 mAh !!
5. I also drilled 2 small holes in the back plate to lead the power lines into the cabinet.
6. I did solder the power lines to the tiny lines of the old power connector and did isolate the joints with shrinking foil.
Then after charging the batteries it was time for testing on my stereo system with my electrostatic Micro Seiki headphone and 24 b 96 I files.
And I must say I am very satisfied with the very clean and dynamic sound.
I am still testing but I expect the batteries to last about 24 hours continuous playing with lossless FLAC 16b 44 k CD quality and ca 12 hours continuous with 24b 96k high res files.
And when the batteries would fail after a few years I just put in a new set of 18650 batteries.
An extra advantage is that the X10 stays a lot cooler probably because there is no dissipation of a battery inside the cabinet...
I realize this is no solution for everyone but I am very satisfied with this somewhat 'nerdy' solution and I saved my X10 from the garbage dump!
I added some photo's to give you an idea of this simple solution.