Another "solution"?
We carry a basic "speaker" a SONY SRS-XB21, its primary use being to listen to music, from our phones, tablets or my PC.
In line with trying to minimise kit lugged about and hassle, we can use it with a 3mm phone jack, from our aging Avtex TV. [Using that connection because the TV does not offer Bluetooth but has a headset output.]
The reality is I very rarely bother, we don't listen to much TV that requires improved audio fidelity, as said that need is found elsewhere.
Plus, the TV is integrated with the vans excellent Pioneer sound system but that is power hungry and is only used when on an EHU.
For catching the news or the odd TV programme that grabs our interest, the Avtex's sound is adequate, without the discontinuity required setting up something better for what is probably of short duration.