I see there is a similar post 3 years. During a live performance T4s audio was cutting out intermittently all channels.
1 sax
2 guitar amp
3 vocal shure
4 vocal
when on break, playing music through 5/6 was unaffected and sounded great.
I was powering the Ts4 through the L1 base stand
The next day I set it up and it worked great, however I was only using 2 inputs. Also played a live performance since with sax on #1 and backing tracks 5/6. worked great
I have had the unit for last least 6 years and have never had a problem.
Any suggestions?