As a certified Geni service tech, I will tell you the conditions you describe could be several different problems. GET A QUALIFIED SERVICE TECH!!!! Luckily, in your case the
unit won't even lift a person, so no personal danger is present. However, be aware that a mal-functioning lift is a potential for serious or fatal injuries. It is not something to ignore or "work around". The things you mention could also be a symptom and not the real problem, I will not attempt to diagnose it from here, just too many things that could be wrong that need a hands on diagnosis.
DuckJordan's analysis was right on. Inspect every time you use it. Check electrical, hydraulic and mechanical. Not a big deal, basically, as he said, do a good look around and check for anything that is different, damaged, out of kilter,
etc.
As for the gentleman who raised the question of "qualified person", my experience has shown over the years that often, "basically, a lot of experience" can trump a recognized degree. Example: your car needs service. Who would you rather do the work? The 19 year old graduate, With a Degree, from the Vo-Tech high school or the mechanic that has worked 20 years for the Penske racing team?