I have #2, but the other person sharing my Internet connection doesn't. A third computer--a laptop--had it both here and elsewhere (though less frequently). There is a switch box (a router, I suppose?) in between, though; I suppose that may make the difference.
Earthen Ring-EU:
Taelas -- 60 Human Protection Warrior; Shaleen -- 52 Human Retribution Paladin; Raethal -- 51 Worgen Guardian Druid; Szar -- 50 Human Fire Mage; Caethan -- 60 Human Blood Death Knight; Danee -- 41 Human Outlaw Rogue; Ainsleigh -- 52 Dark Iron Dwarf Fury Warrior; Mihena -- 44 Void Elf Affliction Warlock; Chiyan -- 41 Pandaren Brewmaster Monk; Threkk -- 40 Orc Fury Warrior; Alliera -- 41 Night Elf Havoc Demon Hunter;
Darkmoon Faire-EU:
Sieon -- 45 Blood Elf Retribution Paladin; Kuaryo -- 51 Pandaren Brewmaster Monk
Taelas -- 60 Human Protection Warrior; Shaleen -- 52 Human Retribution Paladin; Raethal -- 51 Worgen Guardian Druid; Szar -- 50 Human Fire Mage; Caethan -- 60 Human Blood Death Knight; Danee -- 41 Human Outlaw Rogue; Ainsleigh -- 52 Dark Iron Dwarf Fury Warrior; Mihena -- 44 Void Elf Affliction Warlock; Chiyan -- 41 Pandaren Brewmaster Monk; Threkk -- 40 Orc Fury Warrior; Alliera -- 41 Night Elf Havoc Demon Hunter;
Darkmoon Faire-EU:
Sieon -- 45 Blood Elf Retribution Paladin; Kuaryo -- 51 Pandaren Brewmaster Monk