B737 Captain reported a loud squealing noise from a cockpit window during the climb. The flight returned to the departure airport and landed overweight.

Narrative

On departure out of ZZZ we heard a loud squealing noise coming from the FOs (First Officer's) window. As we climbed the noise got worse and cockpit communication both intercom and with ATC became difficult. We asked for a level off at 14000 and were given radar vectors in ZZZ airspace while we trouble shot. We confirmed pressurization and system status. We inspected as much as we could for possible cord in the window but could find nothing. Airplane had come from the hanger right after a Captain window change but also had a write up with an issue on the FOs window. Dispatch was contacted via ACARS and ultimately VHF. We could hardly hear Dispatch due to the noise but we communicated that we were returning to ZZZ and would request priority handling due to being overweight. We diverted back to ZZZ uneventfully after running applicable non normals and checklists. Landing and rollout was normal and we taxied to the gate uneventfully.