Multiple SPI reads slows down read time dramatically
I found the error. Unfortunately I was so busy blaming the code and assuming it was my lack of arduino knowledge that I forgot to check the hardware specs. I thought I was using the maximum external oscillator frequency(f_EOSC) of 300KHz, but in fact was using the 50Hz internal oscillator frequency with an external f_sck from the arduino. This means that the conversions where in fact running at expected times. The thing that threw me off was that the first reading was much faster than the rest. This was most likely because at first read I only had to wait for one channel conversion as the other was already done before I request the data and so the first readings wait time is only as long as a single channels conversion. I would need to implement a 300KHz external clk if I want faster conversion speeds. Thanks for the help for those who tried:)