Episodes of redness in face (mostly cheeks) with a burning warm feeling. dont seem to be triggered by anything specific?

Your body/face is talking to you. Take good notes such as what your were eating/drinking/doing before it happened. Coffee, cold medicine? Then show to your Drs.

Your increased blood flow to your face apparently isn't triggered by anxiety,stress,foods, medications,alcohol,embarrassment, etc. In this situation we look for hormonal causes and conditions like Cushing's syndrome & carcinoid come to mind. I recommend consulting an endocrinologist for evaluation & advice. Appropriate testing will be done if deemed advisable by the consultant.