Joy Dayle Wessels was convicted of unauthorized use of a credit card, 18 U.S.C. § 1029(a)(2). She was sentenced to 12 months’ imprisonment and three years’ su*914pervised release. Later, the district court1 revoked her supervised release, imposing a sentence of 12 months’ imprisonment and 24 months’ supervised release. Wessels appeals, asserting a Fifth Amendment right to due process. Having jurisdiction under 28 U.S.C. § 1291, this court affirms.
At the revocation hearing, Wessels stipulated to violations of her supervised release. During the hearing, she learned that the probation officer, Sylvia A. Gruen-bacher, had disclosed the sentencing recommendation to the government — but not to her — despite her counsel’s specific request for it. The government offered support of “Miss Gruenbacher’s recommendation to the court,” while Wessels’s counsel said, “I don’t even know what the recommendation is.” The court stated that the recommendation was “18 months with 18 months of supervision to follow.” Wes-sels’s counsel noted “for the record, we tried to obtain what the position is, the government and probation.”
Wessels argues that the ex parte communication between the probation officer and the government violated her due process right to a fair tribunal. This court reviews claims of constitutional error de novo. United States v. Washington, 318 F.3d 845, 854 (8th Cir.2003). Due process requires that a trial proceed before a judge with no actual bias against the defendant or interest in the outcome of the particular case. Veal v. Iowa Corr. Inst. for Women, 274 F.3d 479, 480 (8th Cir. 2001). The appearance of bias may also be a ground for disqualification. Ryan v. Clarke, 387 F.3d 785, 793 (8th Cir.2004). The situation must be one “in which experience teaches that the probability of actual bias on the part of the judge ... is too high to be constitutionally tolerable.” Kinder v. Bowersox, 272 F.3d 532, 540 (8th Cir.2001), quoting Withrow v. Larkin, 421 U.S. 35, 47, 95 S.Ct. 1456, 43 L.Ed.2d 712 (1975).
Here, the record shows no actual bias, or appearance of bias, from the ex parte communication. The district court found that the communication between the government and the probation office was irrelevant to the sentencing decision, concluding: “It doesn’t matter. It’s my decision to make at any rate.”
Wessels also contends that the probation officer and the government based their recommendations on unproven and uncharged allegations of criminal activity, violating due process and Federal Rule of Criminal Procedure 32.1(b)(2). No violations occurred. Although Wessels’s counsel noted “there is [sic] some additional allegations out there,” the record shows that the district court properly based the sentence on the stipulated violations of supervised release, not unproven or uncharged criminal activity. See United States v. Davies, 380 F.3d 329, 333 (8th Cir.2004) (finding no violation of Federal Rule of Criminal Procedure 32.1(c) or due process because the “fact that the probation officer might have been motivated by comments received from an unknown Bureau of Prisons employee does not change the fact that the district court properly relied on information contained in the pre-sentence report to justify the modified conditions.”).
The judgment of the district court is affirmed.
. The Honorable Gary A. Fenner, United States District Judge for the Western District of Missouri.