The ham radio restarts when the push to talk button is released

I have installed a new Kenwood TM-281A ham radio in my car. The power is filtered by a Kenwood PG-3B noise filter. When I opened the package of the noise filter, I have noticed some burnt smell but did not pay much attention. The radio transmitted perfectly, but when I released the push to talk button, the radio turned off for a fraction of a second, then turned on again.  When I disconnected the noise filter, the radio started to continuously work again. It is interesting, that a faulty noise filter can supply enough current for the transmission, but cause problems when the current is suddenly reduced.

The sales person at the ham radio store suggested, that most likely the capacitor was faulty. I have returned the noise filter to the store, and when I tested the radio without it, I noticed, that I do not need it for clean, noiseless transmission.