One of the stark contrasts between radio and television, and I’ve been an engineer in both industries, is the attention and detail applied to audio.
In television, even before hubbing and extensive remote controlling of just about everything, a television program chain passes through so many stages (compared to radio) that many times, the ideal feed levels of audio can be either attenuated or amplified, resulting in less or more signal hitting the final stages before being transmitted to air or fed to cable distribution.
The networks are generally more at fault these days than ever before because they have so many affiliates under complete remote control (not that it can’t be bypassed or adjusted locally), but since most of the folks that would be capable of doing that have been downsized, the controls are remoted and hubbed and the changes in level from program to commercials to network to local are largely fixed after being supposedly balanced. Networks can change their satellite transponder and switch all the network satellite receivers at the affiliates remotely, and sometimes do that for once reason or another, and introduce a new set of devices into the program chain at each affiliate, causing video and audio anomalies due to processing not being set up in advance and thusly being hit with too much or not enough signal.
Not to mention the FCC clamping down on loud commercials. Audio processing set to less than ideal attack and release settings can make things real soft or loud depending on which switching occurs, and the usual excuse is that “it’s all digital now” and there is no control over that. If you believe that, I got a bridge in Alaska to sell you.