1. The latest X-series still only counts up the time per track, but as a compromise it also displays the time length of the song being played. Guess Sony was too lazy (or cheap...or didn't think it was a problem) to rewrite their firmware to add the display option of counting down the song play time.
2. You should already have this on your player. Your A729 is quite similar to my A829; on my player, I just hold down on the skip forward side (right) of the main square control to get the FF function. Doing the same on the left side gets the rewind function.
3. Still a no-go on my X-series. I don't know how many manufacturers include a delete function on their current lineup of devices (not Sony, not Apple, and I believe not Microsoft), but the only device I currently own that has this is my Zen X-Fi.
4. You should be able to do this with your A729. Depending on which version of Windows you're using (as I just bought a new name-brand computer I'm still learning where everything is in Vista; my main music/media/DAP manager 'puter is an XP Pro box), you can redesignate how Windows will see your A729, either as a media transfer protocol MTP device (default) or mass-storage UMS/MSC device ("drive"). In XP, connect your A729 and go to My Computer> Properties> Hardware Tab> Device Manager. Select your Walkman and go through the options to make the switch...simple as that. If your running Vista, I suspect it's probably just as simple, but since I've got less that a couple of hours running this new Dell (and most of that was Windows Update patching the OS and Office), I haven't spent any time looking around at how the OS and its functions are organized.
Once done, your A729 should now show up in Windows File Explorer (or any other file manager) with a drive letter assigned to it. Reversing the process is just as easy, only now you'll have to select the correct UMS device/drive instead. I did this with my new X-series, and in generally it works well though it's still not all that fast in terms of file transfers (flash-based devices are just that way, I guess). You should probably back up any content you don't want to lose on your A729 just in case before doing this, but when I did the switch on my player I believe it didn't even impact any of the songs that I'd already loaded on it when it was still in its MTP configuration (no guarantees, though...in my case I only had a couple of dozen or so songs loaded and I didn't care if they were affected by the changeover).
My Sony NWZ-A729 has great sound, but it lacks some features.
Do the newer Sony players have any of these features that the A729
lacks?
1. Display of time remaining on a track
2. Ability to fast forward within a track
3. Ability to delete a track (or flag a track for delete) as it is
playing. With the A729, you have to be connected to a PC to delete
4. Ability to assign a Windows drive letter to the player's drive
so that one can use command line tools to view and manipulate
files on the player - or at least some way to copy a directory
listing of the player's drive to a file, so one can record what's
on the player

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