We’d probably need to hear a recording. All the digital systems are lower audio fidelity than analogue. Most are pretty close but there is a learning curve to get 100% communications. A bit like hairband, where the narrow bandwidth, higher signal to noise and fast speech means it’s more tricky for beginners to listen to than say, Marine band. Some digital systems do sound very robotic, while others are more natural. Some are frankly horrible. Good quality DMR is perfectly workable once you get used to it. A recording would let us establish how bad and untypical it is? However - with digits, if speech is there, then there’s probably no fault, and the weird sound is just the system you bought’s normal sound.