Jason over at Pocket PC Thoughts has posted some good advice on the eternal question of sync-charge cables - something which comes up regularly here, especially in relation to the XDA II / i-mate Pocket PC Phone. A short quote:

"Here's some free advice for all Pocket PC owners: just because a cable fits into the plug, that doesn't mean it's doing what it's supposed to be doing.  Case in point: I had a Boxwave miniSync cable for an XDA, and when I client of mine bought an iMate2 (XDA2) from Tek 'n Toys, I gave her the miniSync cable because she was looking for a mobile charging solution. I tested the miniSync cable on the iMate2 and it was physically compatible, and also charged the unit - the light came on and the Pocket PC said it was charging. My client used this XDA miniSync cable to recharge her device overnight, and the next morning the iMate2 was completely dead. What happened?"

You'll have to read his full post at Pocket PC Thoughts, but I'll talk about my own story first.

I have a mix of cables, and I don't know which is which. I just use whatever's to hand, and if in doubt - it's a simple matter of charging before I hit the <40% limit at which the battery seems to start discharging, or waiting until the device is around 5% battery (at which point it seems to charge happily). My wife's i-mate Smartphone2 has just the same issue.

I've not tested the issue since I've been running the new ROM version - why? Because my Arkon PDA Mount seems to now be working perfectly... that's right, it doesn't discharge since going to the new ROM. So I tend not to need the sync-charge cables, and since going to Bluetooth ActiveSync, I leave my i-mate in its cradle (which is only connected to AC power) and sync over the air. I've been maintaining that the 1.60 and above ROMs seem to fix the decharge issue - at least, the O2 Asia 1.60 extended ROM does - but this may be a faulty assumption.

Just because my issue is fixed does not automatically mean that all sync-charge cables will cease to decharge the XDA II / i-mate Pocket PC. I'm waiting on a ROM update for Emma's i-mate Smartphone2 to see if it fixes the decharge problem for her. And I have yet to test it with my myriad of sync-charge cables. Jason points out a very important point here; don't assume that your sync-charge cable will work. Best to buy the right tool for the job!

Read Jason's full post here.