Here's the modded job also showing the RF out mod
Another top mod by Boss Watts
This unit uses a clever audio detect system to power down in the absence of audio. It seems to take a sum of the audio, probably from the MPX output and apply this to the processor chip, (both are in the black blob under display), and times out in exactly 1 minute if no audio is detected; probably using the RTC (real time clock). This results in total lock-out and all power has to be removed for a short period before it can be re-powered again.
Although similar to the Belkin TuneCast II, the mods for these don’t work here.
The fix is to ‘borrow’ a 50Hz square wave from the display clock, using a 100n ceramic capacitor and a 10K resistor in series. This fools the processor with a suitable signal. Just connecting to the track in the picture works but pulses can be heard on the FM signal; so the track has to be cut, best done using a 1mm drill to cut it away as it goes into the plated through hole as shown.
Here's the modded job also showing the RF out mod