Can a defendant in a criminal case substitute counsel for a new counsel when there is a conflict of interest?

"While a defendant has a right to counsel of his choice under the Sixth Amendment, it is not an absolute right. Absent a conflict of interest, a defendant in a criminal case does not have the unfettered right to retain new counsel." United States v. Brumer, 528 F.3d 157, 160 (2d Cir. 2008) (internal quotation marks and ellipsis omitted). "In determining whether to allow a defendant to retain new counsel, the court must consider the risks and problems associated with the delay, and whether substitutions would disrupt the proceedings and the administration of justice." Id. (internal quotation marks and ellipsis omitted). We review a district court's denial of a request to substitute counsel for abuse of discretion. Id. at 161.