What is the test for a waiver of a defendant's right to attend a section 1203.2a hearing?

We conclude that defendant validly waived his right to be present at the section 1203.2a hearing through counsel. But even if there was not a valid waiver of defendant's right to be present at the section 1203.2a proceeding, and that this amounted to federal constitutional error, the error was harmless. "Under the federal Constitution, error pertaining to a defendant's presence is evaluated under the harmless-beyond-a-reasonabl-doubt standard set forth in Chapman v. California (1967) 386 U.S. 18, 23 [(Chapman)]." (People v. Davis (2005) 36 Cal.4th 510, 532.)³