Ammeter scale, not sure what my amp reading is
I am trying to figure out how much amps are drawn from my small entertainment system ...

I think you mean drawn by my small entertainment system.

My Ammeter's lowest scale is 200.

Presumably you mean 200 A. But maybe you mean 200 mA?

When clamping around the lead that feeds the whole setup (multi plug), I am getting a reading of 00.3 to 00.4 on the screen (scale, 200).
I would normally assume that this is 0.4 AMPS . However, that seems low?

That seems OK for an entertainment system.

... that converts to about 88 watts.

You haven't told us if the system was quiet or running at max volume.
The meter (which you also forgot to specify) probably has an accuracy specification of +/- 5% of full scale (so 5% of 200 whatever units you're using) on AC +/- 2 or 3 digits so your reading will have very poor accuracy.
If the meter is clamp on then make ten turns of your live or neutral wire through the clamp and take the readings again. Divide the reading by ten to get the current.

Figure 1. The meter in question has only got AC A ranges for 200 A and 1000 A AC. Rather unusually the meter has 180° symmetry on the range selector switch.
This is really the wrong meter for the job but there is plenty of room to wind as many turns as you can into the clamp to improve the reading accuracy.