Another useful tip... Turn off everything you can in the camera, shoot only in raw no jpeg... Turn off pretty much (read all) in camera processing of any kind..including noise reduction, it's uneccessry for what you are doing & adds electronic noise & contributes to sensor heat.
Also, hop on eBay & find yourself a 'dummy' battery, mains adapter.... You can use it as is connected to 240v or, check the DC requirement for eos1100d & look for a DC regulator, then you can run it off 12v battery.
For example, my 70d wants 8.1v so, I have a regulated output on my power distribution box that can be varied, it's set to 8.1v... check for the 1100d it may want less or might want more, it matters... A lot!!...
Why do this I hear you ask, more noise & heat reduction
These small things will add up & assist in dropping the noise levels in your subs significantly for a very modest outlay if you go the dummy battery path or, totally free if you discount that...