I just bought an NWZ-X1061, and after some fooling around, I got it to work on Ubuntu 9.04 using libmtp8 0.3.6 compiled from source.
I added the following line to music-players.h:
{ "Sony", 0x054c, "Walkman NWZ-X1051/NWZ-X1061", 0x0398, DEVICE_FLAG_UNLOAD_DRIVER },
While the device continues to be detected as a storage drive by Ubuntu, I got it to work with Rhythmbox and Gnomad2 by...
2009-07-06 01:03:36 UTC in libmtp