I saw a Grey-bellied Bulbul (Pycnonotus cyaniventris cyaniventris) making calls and managed a very short recording of two different calls (above).
The song and calls of this bird are possibly more varied than currently known. The audio recording (edited with some noise reduction) and sonogram/waveform (above) show two types of calls – a lively pipping call rendered “pi-pi-pi-pi…” (Wells 2007) and another softer “wit-wit-wit…” (HBW 2019). Call recording here: https://www.xeno-canto.org/456756
Amar-Singh HSS (Dato’ Dr) – Ipoh, Perak, Malaysia
Location: Taiping, Perak, Malaysia
Habitat: Primary jungle at foothills
Date: 14th February 2019
Equipment: Nikon D500 SLR with Tamron SP 150-600mm f/5-6.3 Di VC USD, handheld with Rode VideoMic Pro Plus Shotgun Microphone