tnCart hangs when running sr.com from slot1 in National CF-3300

[herraa1]

Luis Felipe Antoniosi reports that his National CF-3300 freezes (and needs a power cycle to recover, a reset doesn't help) when running SR.COM (SofaRun) after booting his WonderTANG! + tnCart RTL on slot1. When the machine hangs, the led blinks continuosly.
If he uses slot2 instead of slot1, then the freeze doesn't happen.
See related thread on MRC.

[buppu3]

Does the phenomenon occur on the CF-3300 in general or only on certain machines?
What is the electrical difference between SLOT #1 and #2 on that machine?

Is the power supply voltage unstable due to prolonged storage accesses and RAM writes?

[herraa1]

I think this issue can be closed. There's no further input from the OP.