NW-S644 connection to pc interrupts for no reason

[Gyumaou]

I've got a walkman model NW-S644 and am using SonicStage CP on Win7 Ultimate x64.

I can connect fine and both sonicstage and windows detects the player and displays everything fine. but when I try to add/remove tracks (via either sonicstage or explorer) I get random connection interrupts and I/O device errors, resulting in the transfer being aborted (after a long delay) and I have to unplug the player and plug it back in to try again. This can happen dozens of times in a row, or I can sometimes transfer dozens of tracks with no problems.

This is quite annoying as transferring an album can take half a day, and there was one time when such an interrupted transfer resulted in a BSOD for my pc, not to mention that I couldn't connect to the walkman for about a day afterwards (both win and sonicstage were saying that the device needs to be formatted before use - fixed itself without nay action on my part the next day).

the cable is new, and I have the latest version of sonicstage.

any help appreciated on what I can do to fix this once and for all.

I can play music just fine. sometimes the tracks that appear to have transferred fine are corrupt at the end (player just skips to next song).

[bazz2011]

Have you tried right clicking a saved mp3 file and sending it to the Walkman?  This works for me with the A845 which is just as well because I cannot install Sony's Contents Transfer software on my computer. The transfered files seem to end up in the correct folder on the Walkman.  Deleting tracks works fine for me.  I'm not using any additional software.

[Gyumaou]

doesn't help me unfortunately 😕

this seems to be independent of how I try to move tracks. I tried via explorer (navigate to removable walkman drive or use "send to") or through sonicstage, there seems to be a random chance the walkman will disconnect and cause an I/O error and remains inaccessible until I unplug and plug it back in.