Initially, I thought the hum and buzz caused by signal cable of the RCA-XLR connection. That was rectified by using a RCA-RCA to the Rowland amp.
With the purchase of a power conditioner, the overall noise floor dropped and vinyl listening is enjoyable. So much so, i decided to get a dedicated tube phono stage. At the same time, i swap back the RCA – XLR connection to the power amp. Guess what, no hum and buzz! This is great swap just for the experiment. That my friend is audio winning.