Party members disappear

Time: October 3, 2013 around 02:00AM CST
Frequency: Sometimes (almost every time I play)
World name: Balmung
Character name/race: Rayne Cerise/Miqo'te
NPC name: N/A
Monster name: N/A
Class/Level: White Mage/39
Party or solo: Party
In-game time: Unknown
Area and coordinates: sunken temple of qarn, and every dungeon leading up to this one, also happens when I party outside of dungeons as well.
Steps:
1. Get into dungeon via Duty Finder as Healer
2. Start the instance, kill a few monsters (5-10). Everything is fine.
3. A random member seems then "stuck" in one place. I can see him using skills, HP is going down and up but he doesn't move at all. Player is in another place than where my screen tells me he is. I can heal with medica if I am by where character really is. I cannot select character to heal once I am close where character really is. If I stand by where my screen tells me character is I am not able to heal because I get interrupted constantly even though nothing is interrupting me and if I go to where character really is I cannot heal either because it won't let me select character. Other members of party can see character.
4. Log out of the game
5. Log in back in the game
6. Member can be targeted and move as normal


Connection Specs
- Type of internet connection/provider : Cable/Charter Internet
- Modem maker/model number : Cisco/DPC3008

Model Number of the PlayStation 3 You Are Using
- Model Number: CECHA01

Additional Information: This also happened to me on Exodus to before I transferred. My boyfriend sits by me and plays on the PC and he never has this problem. He is also able to tell me the actual location of the player and that is how I use medica to heal.