That is very common - often different takes are spliced together or a mistake is over dubbed.
See this link
I would say you can hear what could be categorized as errors on at least one third of what you buy. The most common is for distortion due to aggressive mastering (limiters) to get things to sound uniformly loud. You can hear when these devices are kicking in and when they don't. Of course, some will argue that it is meant to sound that way...
See this link
I would say you can hear what could be categorized as errors on at least one third of what you buy. The most common is for distortion due to aggressive mastering (limiters) to get things to sound uniformly loud. You can hear when these devices are kicking in and when they don't. Of course, some will argue that it is meant to sound that way...