“HTC has put up a new ROM update (click here for the download instruction) for the HTC Touch Diamond generic version, which will solve some software bugs on video playback and camera. The ROM has a version number of 2.03.401.3, you could check your device info if you need an upgrade.
When you launch the Camera while the system is working on other programs, the preview screen may become black.
When playing a video, sometimes a portion of the video will be cut off a little bit.
Fixes Audio playback problem with the speaker. Specific issues: sometimes the music will turn off and on after 10 minutes, or there is a buzzing sound or no sound at all.
Fixes the problem of not being able to receive MMS when in standby mode.
When launching music via the Music tab on TouchFLO 3D, the sound may intermittently turn off for a second and come back on.” via slashphone.com
Here is a detail change log of the upgrade: