Sinead O'Connor may represent herself in legal actions brought against her by former manager Fachtna O'Ceallaigh for alleged breach of contract and defamation, the High Court heard.
The Dublin singer denies the claims.
Mr Justice Seamus Noonan was told she no longer wished to be represented in the proceedings by her current legal team.
John Gordon, for Mr O'Ceal-laigh and for a company he owns and controls, TAL Management, said this was the third time the singer had "fired" the lawyers she had engaged to defend the proceedings.
He is seeking €500,000 for a breach of contract.
Counsel said his clients had brought a pre-trial application seeking to have the defamation and breach of contract cases heard by the same judge, having forgone the option of the case being heard before a jury.
Mr O'Ceallaigh and his company want the case heard as soon as possible.
Counsel said the singer was "manipulating the system" in proceedings that began in 2012.
It had taken his clients two-and-a-half years to get 50 documents through discovery.
Counsel said Ms O'Connor sent his client and his solicitor "several abusive emails". In one, she said she was going to represent herself.
The judge, noting the situation, adjourned the matter to October for case management.
He said the hearing of pre-trial issues in the cases would go ahead on that date, irrespective of whether the singer had "no solicitor or a new solicitor".
Mr O'Ceallaigh and TAL claim the firm provided managerial services for several years for an agreed monthly fee plus commission and expenses.
In 2011, it is claimed, the company was substituted for Mr O'Ceallaigh under a new agreement.
While it was not executed, it is claimed the parties performed the terms of the new agreement.
Mr O'Ceallaigh claims that without warning, the agreement was ended in April 2012.
It is claimed Ms O'Connor was not entitled to do that, and he seeks upwards of €500,000 for breach of contract as well as a declaration that the management agreement was not validly terminated.
The singer denies she ever had an agreement with TAL or Mr O'Ceallaigh as alleged or that he and the company are entitled to damages. She also denies defaming him.