Telefunkin TVC 240 Camcorder

Telefunkin TVC 240 camcorder builtin microphone sucks. Bought two of them and only found out much later about the insensitive mic. Records at pathetically low volume. Asked them if it can be replaced with more sensitive camcorders for better audio recording. I even offered to pay the difference in price. No response. Absolute silence. I will never again buy a Telefunkin product.