Cheaper Alternative ESC for MM/8xl E-maxx??

[BrianG]

That usually means they are poor quality cells, or the cells are heating up too much. High heat kills NiMHs quickly. If the gearing is set correct (meaning: not too aggressive), hot NiMHs means they have high internal resistance and aren't suitable for the currents required. So, either way, they don't sound all that good for BL IMO - probably fine for stock Titans though...