Thanks for clearing that up man.

Guys... *deep breath*

GSM/EDGE DOES NOT SUPPORT SIMULTANEOUS DATA AND VOICE.

Go google. It either drops ACTIVE data when calls come in, or holds ACTIVE data and drops calls (depending on the mode it's running on).

E being displayed on the status bar and whatsapp running (for instance) DOES NOT MEAN IT'S DOWNLOADING/UPLOADING ALL THE TIME.

To try, download something big on EDGE. Then call yourself. Voila.

ONLY WCDMA and above (HSPA) supports simultaneous data and voice. Oh, and WIFI obviously.

As a solution to the jumping issue, try this: type *#301279# in the dialer, select HSPA revision, and select no 2. Now press on your menu button and select END. Lastly, turn flightmode on and off to refresh.

Now HSUPA is off, and it jumps less. You WILL NEVER EVER SEE H OR H+ in the status bar any more (as HSUPA - the upload part - has been turned off), but download speeds shouldn't be effected by much (HSDPA is still on), EVEN if it ONLY shows 3G.

To return to your normal config, redo the whole thing but select number 3 in HSPA revision menu. Or you can go hardcore 3G only and select 1 to turn off both HSDPA and HSUPA off.

Have fun.