The most likely causes are settings and color management, not a fault with the camera.

Common reasons include:

• Color mode/picture style set too aggressively. Consumer cameras often boost color for more “pop.” On the HX100V, check the Color mode; if it’s on Vivid, that can easily cause oversaturated, warm-looking results.
• White balance may be incorrect, which can create a red or warm cast.
• Saturation settings may be turned up.
• Color space/profile issues. If the camera is set to AdobeRGB but you’re viewing/editing without proper color management, colors can look wrong. sRGB is usually the safest choice.
• Display calibration. An uncalibrated monitor can make images appear too red or too vivid.

What to try:

1. Set Color mode to Standard or a more natural option.
2. Use Auto White Balance or set WB manually for the scene.
3. Reduce any saturation boost.
4. Set the camera to sRGB unless you use a fully color-managed workflow.
5. Compare the same image on another screen.

If you want more specific diagnosis, compare sample images from the same camera model or test with a few controlled shots.