Do an xperiment. It will cost you about $150.
Buy a Schiit Mani, configure it for MC and feed the phono out into the Mani, instead of the Urika. Feed Mani output to your amp. If the sound improves, it is the Urika's problem. If the sound is the same, it is the cartridge's problem.
Buy a Schiit Mani, configure it for MC and feed the phono out into the Mani, instead of the Urika. Feed Mani output to your amp. If the sound improves, it is the Urika's problem. If the sound is the same, it is the cartridge's problem.