Syncing Endomondo

It seems the old Help section has disappeared, and the one I posted on is difficult to find. Even I couldn't find where I'd posted my question a week ago, and I'd quite like to sort this problem out. So, here it is:

I have my Endomondo synced to MFP, but quite often (if not daily) it will double the time and calories burned. For example, if I've walked for 41 minutes and burned 275 calories, MFP posts it as 82 minutes and 550 calories. Consequently putting my entire diary out of sync. It only does this with MFP, it posts the correct times/burn to Facebook, and also to the Endomondo site.

I used to use Runkeeper, but I found that it would stop halfway, or not track my entire walk (I do the same walk routinely, so I know the distance). However, I'm not sure if that was Runkeeper or my phone, but when I installed Endomondo on the same phone, it worked perfectly.

I DO now have a different phone, but this began before I changed mobiles. I prefer the ease of Endomondo, so if anyone (or MFP) have any ideas, I'd appreciate them. Otherwise I guess I'll be reinstalling Runkeeper and trying it out for size again. Thanks