Chord errors, pedal losing calibration, and can't load MP3

[Obijohn]

I have had a few months of very positive experience with a Pa5x and just bought an 'open-box' unit that is starting to give me some problems.
1. At least once a week, the DS-1H sustain pedal stops working and I need to recalibrate it.
2. Yesterday it started displaying the wrong chords across the top. It was showing all chords a fourth higher than what I was playing. I looked for any transpose features that might have been turned on and restarted the unit without success. Twenty minutes later it started showing the correct chords again for no apparent reason.
3. On the previous Pa5x, I recorded about 25 songs in MP3 which I loaded into my Apple Music files. As soon as I got the new Pa5x, I used a USB drive to load the folder onto the new Pa5x and stored them on the microSD card I installed. it worked great at first and all the songs played. Yesterday, I tried to play those same MP3 files and got a pop-up saying, "Can't Load File." The only way I can play these files now is by loading them into a Jukebox folder which is not an ideal solution but it does show that the files are intact.

My dilemma is whether these are user-error issues or whether I should return this keyboard during the 30-day window and get a new one that is factory-sealed.

Appreciate any advice.

[Giner]

I wouldn't mess about. You've got a 30-day window, use it.

[karmathanever]

I would start by downloading a fresh copy of the latest OS onto a new USB and re-load the OS.
Also, it might be worth replacing the microSD

If that doesn't work, I would definitely take Giner's advice

Hope you get it fixed