"No sound from headphones?"に関する回答I would suggest buying new head phones. You can also clean the headphone jack with a q-tip.
"SD Card removed unexpectedly"に関する回答From what you are saying in your statement the issue is within the SD card it self. I would suggest trying to save any data possible in the SD card and with the purchase of the new card transfer the data. If that is not possible, Just replace the old SD card with a new. I would suggest purchasing a SanDisk SD card or a Samsung evo+.