Traineeship Red Flags

I recently began working as a trainee solicitor. However, I have become increasingly worried for the following reasons;

- my employer paid me a few weeks late despite numerous polite requests from me. Other employees have experienced similar delays/issues at different times.

-I was not provided with my first pay slip (despite requesting same twice).

-I have been told through the grapevine the firm did not pay a previous trainee (who worked in the firm prior to ppc1) any salary/allowance during the ppc1 (despite the Law Society rules requiring a salary to be paid) AND expected the trainee to come in and work during PPC1 (again contrary to Law Society rules)

I am wondering is this behaviour commonplace? Should I begin looking elsewhere? I have 8 FE1s so I am eligible for ppc1 in september.