I haven’t done much with trying to convert mp3 back to lossless, but I did experiment with one program a few years ago and couldn’t perceive any difference after doing the “conversion”. My gut feeling is once you have stored the files as mp3 the missing 93% of bits that have been discarded can’t be resurrected with any algorithm.
My advice is to enjoy your new portable player streaming Amazon High Rez and listening to your mp3 files, which will probably sound pretty good on the player. Buy a few High Rez downloads as funds allow and then re rip your CDs to FLAC when you return home. If you keep trying to push the genie back in the bottle you will be frustrated and it will take some of the pleasure out of owning the new player
My advice is to enjoy your new portable player streaming Amazon High Rez and listening to your mp3 files, which will probably sound pretty good on the player. Buy a few High Rez downloads as funds allow and then re rip your CDs to FLAC when you return home. If you keep trying to push the genie back in the bottle you will be frustrated and it will take some of the pleasure out of owning the new player