The glitch I'm talking about is after the end of the theives guild questline. If the player does not complete all of the minor misc. quests for the guild before the last quest of the questline, then Brynjolf will keep repeating that line over and over again. There is no way to fix it that I know of. Normally, Brynjolf should have given the player the quest that would have led to them officially becoming head of the guild. The glitch actually happened to me... =/
it's not a glitch...in order to become the head of the guild you have complete a ton of misc. quests..which you can do easily by just taking jobs over and over from delvynn..eventulaly he'll ask you to do certain special tasks..once you've completed 4...one for each hold & return everyone will say taht he wants to speak with you..so..you're game isn't glitched..you just haven't finished what you have to do yet.
I did that. It's a glitch. =/ From USEP: "If the player completes the main story arc before doing the side and improvement quests for Vex and Delvin, Brynjolf may not interact with the player and instead repeat that he is busy and that he will talk to you later. Consequently, becoming the Guildmaster will be rendered impossible." Go there yourself, look under the quest "Under New Management", and you'll see it under the bugs section. I'm not the only one with the issue.